53 results on '"Renate K. Hukema"'
Search Results
2. Reduction of Fmr1 mRNA Levels Rescues Pathological Features in Cortical Neurons in a Model of FXTAS
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Malgorzata Drozd, Sébastien Delhaye, Thomas Maurin, Sara Castagnola, Mauro Grossi, Frédéric Brau, Marielle Jarjat, Rob Willemsen, Maria Capovilla, Renate K. Hukema, Enzo Lalli, and Barbara Bardoni
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Therapeutics. Pharmacology ,RM1-950 - Abstract
Fragile X-associated tremor ataxia syndrome (FXTAS) is a rare disorder associated to the presence of the fragile X premutation, a 55–200 CGG repeat expansion in the 5′ UTR of the FMR1 gene. Two main neurological phenotypes have been described in carriers of the CGG premutation: (1) neurodevelopmental disorders characterized by anxiety, attention deficit hyperactivity disorder (ADHD), social deficits, or autism spectrum disorder (ASD); and (2) after 50 years old, the FXTAS phenotype. This neurodegenerative disorder is characterized by ataxia and a form of parkinsonism. The molecular pathology of this disorder is characterized by the presence of elevated levels of Fragile X Mental Retardation 1 (FMR1) mRNA, presence of a repeat-associated non-AUG (RAN) translated peptide, and FMR1 mRNA-containing nuclear inclusions. Whereas in the past FXTAS was mainly considered as a late-onset disorder, some phenotypes of patients and altered learning and memory behavior of a mouse model of FXTAS suggested that this disorder involves neurodevelopment. To better understand the physiopathological role of the increased levels of Fmr1 mRNA during neuronal differentiation, we used a small interfering RNA (siRNA) approach to reduce the abundance of this mRNA in cultured cortical neurons from the FXTAS mouse model. Morphological alterations of neurons were rescued by this approach. This cellular phenotype is associated to differentially expressed proteins that we identified by mass spectrometry analysis. Interestingly, phenotype rescue is also associated to the rescue of the abundance of 29 proteins that are involved in various pathways, which represent putative targets for early therapeutic approaches. Keywords: FXTAS, premutation, Fmr1 mRNA, dendritic arborization, Tia1, ROAA, Hnrnpll, Aldh4a1/P5CDH, dendrtic spine
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- 2019
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3. Astroglial-targeted expression of the fragile X CGG repeat premutation in mice yields RAN translation, motor deficits and possible evidence for cell-to-cell propagation of FXTAS pathology
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H. Jürgen Wenzel, Karl D. Murray, Saif N. Haify, Michael R. Hunsaker, Jared J. Schwartzer, Kyoungmi Kim, Albert R. La Spada, Bryce L. Sopher, Paul J. Hagerman, Christopher Raske, Lies-Anne W.F.M. Severijnen, Rob Willemsen, Renate K. Hukema, and Robert F. Berman
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FXTAS ,Fragile X premutation ,Mouse model ,Neurodegeneration ,Glia ,RAN translation ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract The fragile X premutation is a CGG trinucleotide repeat expansion between 55 and 200 repeats in the 5′-untranslated region of the fragile X mental retardation 1 (FMR1) gene. Human carriers of the premutation allele are at risk of developing the late-onset neurodegenerative disorder, fragile X-associated tremor/ataxia syndrome (FXTAS). Characteristic neuropathology associated with FXTAS includes intranuclear inclusions in neurons and astroglia. Previous studies recapitulated these histopathological features in neurons in a knock-in mouse model, but without significant astroglial pathology. To determine the role of astroglia in FXTAS, we generated a transgenic mouse line (Gfa2-CGG99-eGFP) that selectively expresses a 99-CGG repeat expansion linked to an enhanced green fluorescent protein (eGFP) reporter in astroglia throughout the brain, including cerebellar Bergmann glia. Behaviorally these mice displayed impaired motor performance on the ladder-rung test, but paradoxically better performance on the rotarod. Immunocytochemical analysis revealed that CGG99-eGFP co-localized with GFAP and S-100ß, but not with NeuN, Iba1, or MBP, indicating that CGG99-eGFP expression is specific to astroglia. Ubiquitin-positive intranuclear inclusions were found in eGFP-expressing glia throughout the brain. In addition, intracytoplasmic ubiquitin-positive inclusions were found outside the nucleus in distal astrocyte processes. Intriguingly, intranuclear inclusions, in the absence of eGFP mRNA and eGFP fluorescence, were present in neurons of the hypothalamus and neocortex. Furthermore, intranuclear inclusions in both neurons and astrocytes displayed immunofluorescent labeling for the polyglycine peptide FMRpolyG, implicating FMRpolyG in the pathology found in Gfa2-CGG99 mice. Considered together, these results show that Gfa2-CGG99 expression in mice is sufficient to induce key features of FXTAS pathology, including formation of intranuclear inclusions, translation of FMRpolyG, and deficits in motor function.
- Published
- 2019
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4. Inducible expression of human C9ORF72 36× G4C2 hexanucleotide repeats is sufficient to cause RAN translation and rapid muscular atrophy in mice
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Fréderike W. Riemslagh, Esmay C. van der Toorn, Rob F. M. Verhagen, Alex Maas, Laurens W. J. Bosman, Renate K. Hukema, and Rob Willemsen
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c9orf72 ,als ,ftd ,mouse ,inducible ,dprs ,Medicine ,Pathology ,RB1-214 - Abstract
The hexanucleotide G4C2 repeat expansion in the first intron of the C9ORF72 gene accounts for the majority of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) cases. Numerous studies have indicated the toxicity of dipeptide repeats (DPRs), which are produced via repeat-associated non-AUG (RAN) translation from the repeat expansion, and accumulate in the brain of C9FTD/ALS patients. Mouse models expressing the human C9ORF72 repeat and/or DPRs show variable pathological, functional and behavioral characteristics of FTD and ALS. Here, we report a new Tet-on inducible mouse model that expresses 36× pure G4C2 repeats with 100-bp upstream and downstream human flanking regions. Brain-specific expression causes the formation of sporadic sense DPRs aggregates upon 6 months of dox induction, but no apparent neurodegeneration. Expression in the rest of the body evokes abundant sense DPRs in multiple organs, leading to weight loss, neuromuscular junction disruption, myopathy and a locomotor phenotype within the time frame of 4 weeks. We did not observe any RNA foci or pTDP-43 pathology. Accumulation of DPRs and the myopathy phenotype could be prevented when 36× G4C2 repeat expression was stopped after 1 week. After 2 weeks of expression, the phenotype could not be reversed, even though DPR levels were reduced. In conclusion, expression of 36× pure G4C2 repeats including 100-bp human flanking regions is sufficient for RAN translation of sense DPRs, and evokes a functional locomotor phenotype. Our inducible mouse model suggests that early diagnosis and treatment are important for C9FTD/ALS patients. This article has an associated First Person interview with the first author of the paper.
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- 2021
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5. Lack of a Clear Behavioral Phenotype in an Inducible FXTAS Mouse Model Despite the Presence of Neuronal FMRpolyG-Positive Aggregates
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Saif N. Haify, Ruchira S. D. Mankoe, Valerie Boumeester, Esmay C. van der Toorn, Rob F. M. Verhagen, Rob Willemsen, Renate K. Hukema, and Laurens W. J. Bosman
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FXTAS ,nuclear inclusions ,mouse behavior ,FMR1 ,repeat expansion ,Biology (General) ,QH301-705.5 - Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a rare neurodegenerative disorder caused by a 55–200 CGG repeat expansion in the 5′ untranslated region of the Fragile X Mental Retardation 1 (FMR1) gene. FXTAS is characterized by progressive cerebellar ataxia, Parkinsonism, intention tremors and cognitive decline. The main neuropathological hallmark of FXTAS is the presence of ubiquitin-positive intranuclear inclusions in neurons and astrocytes throughout the brain. The molecular pathology of FXTAS involves the presence of 2 to 8-fold elevated levels of FMR1 mRNA, and of a repeat-associated non-AUG (RAN) translated polyglycine peptide (FMRpolyG). Increased levels of FMR1 mRNA containing an expanded CGG repeat can result in cellular toxicity by an RNA gain-of-function mechanism. The increased levels of CGG repeat-expanded FMR1 transcripts may create RNA foci that sequester important cellular proteins, including RNA-binding proteins and FMRpolyG, in intranuclear inclusions. To date, it is unclear whether the FMRpolyG-positive intranuclear inclusions are a cause or a consequence of FXTAS disease pathology. In this report we studied the relation between the presence of neuronal intranuclear inclusions and behavioral deficits using an inducible mouse model for FXTAS. Neuronal intranuclear inclusions were observed 4 weeks after dox-induction. After 12 weeks, high numbers of FMRpolyG-positive intranuclear inclusions could be detected in the hippocampus and striatum, but no clear signs of behavioral deficits related to these specific brain regions were found. In conclusion, the observations in our inducible mouse model for FXTAS suggest a lack of correlation between the presence of intranuclear FMRpolyG-positive aggregates in brain regions and specific behavioral phenotypes.
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- 2020
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6. In silico, in vitro, and in vivo Approaches to Identify Molecular Players in Fragile X Tremor and Ataxia Syndrome
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Saif N. Haify, Teresa Botta-Orfila, Renate K. Hukema, and Gian Gaetano Tartaglia
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RNA ,Fragile X associated tremor ataxia syndrome (FXTAS) ,mouse model ,computational modeling ,protein network ,Biology (General) ,QH301-705.5 - Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative monogenetic disorder affecting carriers of premutation (PM) forms of the FMR1 gene, resulting in a progressive development of tremors, ataxia, and neuropsychological problems. This highly disabling disease is quite common in the general population with an estimation of about 20 million PM carriers worldwide. The chances of developing FXTAS increase dramatically with age, with about 45% of male carriers over the age of 50 being affected. Both the gene and pathogenic trigger, a mutant expansion of CGG RNA, causing FXTAS are known. This makes it an interesting disease to develop targeted therapeutic interventions for. Yet, no such interventions are available at this moment. Here we discuss in silico, in vitro, and in vivo approaches and how they have been used to identify the molecular determinants of FXTAS pathology. These approaches have yielded substantial information about FXTAS pathology and, consequently, many markers have emerged to play a key role in understanding the disease mechanism. Integration of the different approaches is expected to provide crucial information about the value of these markers as either therapeutic target or biomarker, essential to monitor therapeutic interventions in the future.
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- 2020
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7. An Integrative Study of Protein-RNA Condensates Identifies Scaffolding RNAs and Reveals Players in Fragile X-Associated Tremor/Ataxia Syndrome
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Fernando Cid-Samper, Mariona Gelabert-Baldrich, Benjamin Lang, Nieves Lorenzo-Gotor, Riccardo Delli Ponti, Lies-Anne W.F.M. Severijnen, Benedetta Bolognesi, Ellen Gelpi, Renate K. Hukema, Teresa Botta-Orfila, and Gian Gaetano Tartaglia
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Biology (General) ,QH301-705.5 - Abstract
Summary: Recent evidence indicates that specific RNAs promote the formation of ribonucleoprotein condensates by acting as scaffolds for RNA-binding proteins (RBPs). We systematically investigated RNA-RBP interaction networks to understand ribonucleoprotein assembly. We found that highly contacted RNAs are structured, have long UTRs, and contain nucleotide repeat expansions. Among the RNAs with such properties, we identified the FMR1 3′ UTR that harbors CGG expansions implicated in fragile X-associated tremor/ataxia syndrome (FXTAS). We studied FMR1 binding partners in silico and in vitro and prioritized the splicing regulator TRA2A for further characterization. In a FXTAS cellular model, we validated the TRA2A-FMR1 interaction and investigated implications of its sequestration at both transcriptomic and post-transcriptomic levels. We found that TRA2A co-aggregates with FMR1 in a FXTAS mouse model and in post-mortem human samples. Our integrative study identifies key components of ribonucleoprotein aggregates, providing links to neurodegenerative disease and allowing the discovery of therapeutic targets. : Cid-Samper et al. analyze protein-RNA networks and identify properties of RNA scaffolds within biological condensates. They find that CGG repeats in the 3′ UTR of FMR1 attract several proteins, including the splicing factor TRA2A that co-aggregates in fragile X-associated tremor/ataxia syndrome (FXTAS). Keywords: phase separation, scaffolding RNA, CGG repeat expansion, FMR1 premutation, fragile X-associated tremor/ataxia syndrome, FXTAS, RNA aggregates, RNA binding proteins, RBP, TRA2A splicing regulator, neurodegeneration
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- 2018
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8. Combination Therapy in Fragile X Syndrome; Possibilities and Pitfalls Illustrated by Targeting the mGluR5 and GABA Pathway Simultaneously
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Shimriet Zeidler, Helen de Boer, Renate K. Hukema, and Rob Willemsen
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Fragile X syndrome ,FMR1 ,GABA ,bumetanide ,mGluR5 ,automated tube test ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Fragile X syndrome (FXS) is the most common monogenetic cause of intellectual disability and autism. The disorder is characterized by altered synaptic plasticity in the brain. Synaptic plasticity is tightly regulated by a complex balance of different synaptic pathways. In FXS, various synaptic pathways are disrupted, including the excitatory metabotropic glutamate receptor 5 (mGluR5) and the inhibitory γ-aminobutyric acid (GABA) pathways. Targeting each of these pathways individually, has demonstrated beneficial effects in animal models, but not in patients with FXS. This lack of translation might be due to oversimplification of the disease mechanisms when targeting only one affected pathway, in spite of the complexity of the many pathways implicated in FXS. In this report we outline the hypothesis that targeting more than one pathway simultaneously, a combination therapy, might improve treatment effects in FXS. In addition, we present a glance of the first results of chronic combination therapy on social behavior in Fmr1 KO mice. In contrast to what we expected, targeting both the mGluR5 and the GABAergic pathways simultaneously did not result in a synergistic effect, but in a slight worsening of the social behavior phenotype. This does implicate that both pathways are interconnected and important for social behavior. Our results underline the tremendous fine-tuning that is needed to reach the excitatory-inhibitory balance in the synapse in relation to social behavior. We believe that alternative strategies focused on combination therapy should be further explored, including targeting pathways in different cellular compartments or cell-types.
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- 2017
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9. Cerebral Protein Synthesis in a Knockin Mouse Model of the Fragile X Premutation
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Mei Qin, Tianjian Huang, Zhonghua Liu, Michael Kader, Thomas Burlin, Zengyan Xia, Zachary Zeidler, Renate K. Hukema, and Carolyn B. Smith
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Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The (CGG)n-repeat in the 5′-untranslated region of the fragile X mental retardation gene ( FMR1 ) gene is polymorphic and may become unstable on transmission to the next generation. In fragile X syndrome, CGG repeat lengths exceed 200, resulting in silencing of FMR1 and absence of its protein product, fragile X mental retardation protein (FMRP). CGG repeat lengths between 55 and 200 occur in fragile X premutation (FXPM) carriers and have a high risk of expansion to a full mutation on maternal transmission. FXPM carriers have an increased risk for developing progressive neurodegenerative syndromes and neuropsychological symptoms. FMR1 mRNA levels are elevated in FXPM, and it is thought that clinical symptoms might be caused by a toxic gain of function due to elevated FMR1 mRNA. Paradoxically, FMRP levels decrease moderately with increasing CGG repeat length in FXPM. Lowered FMRP levels may also contribute to the appearance of clinical problems. We previously reported increases in regional rates of cerebral protein synthesis (rCPS) in the absence of FMRP in an Fmr1 knockout mouse model and in a FXPM knockin (KI) mouse model with 120 to 140 CGG repeats in which FMRP levels are profoundly reduced (80%–90%). To explore whether the concentration of FMRP contributes to the rCPS changes, we measured rCPS in another FXPM KI model with a similar CGG repeat length and a 50% reduction in FMRP. In all 24 brain regions examined, rCPS were unaffected. These results suggest that even with 50% reductions in FMRP, normal protein synthesis rates are maintained.
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- 2014
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10. Small molecule 1a reduces FMRpolyG-mediated toxicity in in vitro and in vivo models for FMR1 premutation
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Saif N Haify, Valerie Boumeester, Rob Willemsen, Lies-Anne Severijnen, Lucas Verwegen, Wang Yong Yang, Ronald A.M. Buijsen, Michael D. Cameron, Helen de Boer, Matthew D. Disney, Roos Monshouwer, Renate K. Hukema, Clinical Genetics, Cell biology, and Erasmus University Rotterdam
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AcademicSubjects/SCI01140 ,Male ,RAD23B ,Ataxia ,Population ,Cell Communication ,Biology ,Fragile X Mental Retardation Protein ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Tremor ,Genetics ,medicine ,Animals ,Humans ,education ,Molecular Biology ,Genetics (clinical) ,030304 developmental biology ,Neurons ,0303 health sciences ,education.field_of_study ,RNA ,Translation (biology) ,General Medicine ,FMR1 ,Small molecule ,DNA-Binding Proteins ,Disease Models, Animal ,DNA Repair Enzymes ,Fragile X Syndrome ,Ran ,Cancer research ,General Article ,medicine.symptom ,Trinucleotide Repeat Expansion ,030217 neurology & neurosurgery - Abstract
Fragile X-associated tremor and ataxia syndrome (FXTAS) is a late-onset, progressive neurodegenerative disorder characterized by tremors, ataxia and neuropsychological problems. This disease is quite common in the general population with approximately 20 million carriers worldwide. The risk of developing FXTAS increases dramatically with age, with about 45% of male carriers over the age of 50 being affected. FXTAS is caused by a CGG-repeat expansion (CGGexp) in the fragile X mental retardation 1 (FMR1) gene. CGGexp RNA is translated into the FMRpolyG protein by a mechanism called RAN translation. Although both gene and pathogenic trigger are known, no therapeutic interventions are available at this moment. Here, we present, for the first time, primary hippocampal neurons derived from the ubiquitous inducible mouse model which is used as a screening tool for targeted interventions. A promising candidate is the repeat binding, RAN translation blocking, small molecule 1a. Small molecule 1a shields the disease-causing CGGexp from being translated into the toxic FMRpolyG protein. Primary hippocampal neurons formed FMRpolyG-positive inclusions, and upon treatment with 1a, the numbers of FMRpolyG-positive inclusions are reduced. We also describe for the first time the formation of FMRpolyG-positive inclusions in the liver of this mouse model. Treatment with 1a reduced the insoluble FMRpolyG protein fraction in the liver but not the number of inclusions. Moreover, 1a treatment had a reducing effect on the number of Rad23b-positive inclusions and insoluble Rad23b protein levels. These data suggest that targeted small molecule therapy is effective in an FXTAS mouse model and has the potential to treat CGGexp-mediated diseases, including FXTAS.
- Published
- 2021
11. Short antisense oligonucleotides alleviate the pleiotropic toxicity of RNA harboring expanded CGG repeats
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Agnieszka Piasecka, Magdalena Derbis, Oliver Stork, Katarzyna Taylor, Renate K. Hukema, Michał Sekrecki, Emre Kul, Daria Niewiadomska, Krzysztof Sobczak, Clinical Genetics, and Erasmus University Rotterdam
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Male ,0301 basic medicine ,congenital, hereditary, and neonatal diseases and abnormalities ,Science ,General Physics and Astronomy ,Mice, Transgenic ,Article ,General Biochemistry, Genetics and Molecular Biology ,Antisense oligonucleotide therapy ,Fragile X Mental Retardation Protein ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Tremor ,Gene expression ,Animals ,Nuclear protein ,Multidisciplinary ,Chemistry ,Oligonucleotide ,Neurodegenerative diseases ,Alternative splicing ,Nuclear Proteins ,RNA ,Translation (biology) ,Exons ,General Chemistry ,Oligonucleotides, Antisense ,FMR1 ,nervous system diseases ,Cell biology ,Alternative Splicing ,MicroRNAs ,030104 developmental biology ,Cytoplasm ,Fragile X Syndrome ,Ataxia ,Female ,Trinucleotide Repeat Expansion ,030217 neurology & neurosurgery ,Neuroscience - Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is an incurable neurodegenerative disorder caused by expansion of CGG repeats in the FMR1 5’UTR. The RNA containing expanded CGG repeats (rCGGexp) causes cell damage by interaction with complementary DNA, forming R-loop structures, sequestration of nuclear proteins involved in RNA metabolism and initiation of translation of polyglycine-containing protein (FMRpolyG), which forms nuclear insoluble inclusions. Here we show the therapeutic potential of short antisense oligonucleotide steric blockers (ASOs) targeting directly the rCGGexp. In nuclei of FXTAS cells ASOs affect R-loop formation and correct miRNA biogenesis and alternative splicing, indicating that nuclear proteins are released from toxic sequestration. In cytoplasm, ASOs significantly decrease the biosynthesis and accumulation of FMRpolyG. Delivery of ASO into a brain of FXTAS mouse model reduces formation of inclusions, improves motor behavior and corrects gene expression profile with marginal signs of toxicity after a few weeks from a treatment., Fragile X-associated tremor/ataxia syndrome is a neurodegenerative disease caused by toxic RNA containing expanded CGG repeats. Here, the authors show that synthetic oligonucleotides targeting the RNA repeats decrease the pleiotropic effect of this toxic molecule in cellular and animal models of the disease.
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- 2021
12. Inducible expression of human C9ORF72 36× G4C2 hexanucleotide repeats is sufficient to cause RAN translation and rapid muscular atrophy in mice
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Alex Maas, Rob Willemsen, Fréderike W. Riemslagh, Renate K. Hukema, Rob F M Verhagen, Laurens W. J. Bosman, Esmay C van der Toorn, Clinical Genetics, Cell biology, and Neurosciences
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Mouse ,Inducible ,DPRs ,Neuroscience (miscellaneous) ,Medicine (miscellaneous) ,lcsh:Medicine ,C9ORF72 ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Atrophy ,Immunology and Microbiology (miscellaneous) ,C9orf72 ,medicine ,lcsh:Pathology ,Amyotrophic lateral sclerosis ,Myopathy ,Neurodegeneration ,lcsh:R ,Intron ,FTD ,medicine.disease ,Molecular biology ,Phenotype ,medicine.symptom ,ALS ,Trinucleotide repeat expansion ,lcsh:RB1-214 ,Research Article - Abstract
The hexanucleotide G4C2 repeat expansion in the first intron of the C9ORF72 gene accounts for the majority of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) cases. Numerous studies have indicated the toxicity of dipeptide repeats (DPRs), which are produced via repeat-associated non-AUG (RAN) translation from the repeat expansion, and accumulate in the brain of C9FTD/ALS patients. Mouse models expressing the human C9ORF72 repeat and/or DPRs show variable pathological, functional and behavioral characteristics of FTD and ALS. Here, we report a new Tet-on inducible mouse model that expresses 36× pure G4C2 repeats with 100-bp upstream and downstream human flanking regions. Brain-specific expression causes the formation of sporadic sense DPRs aggregates upon 6 months of dox induction, but no apparent neurodegeneration. Expression in the rest of the body evokes abundant sense DPRs in multiple organs, leading to weight loss, neuromuscular junction disruption, myopathy and a locomotor phenotype within the time frame of 4 weeks. We did not observe any RNA foci or pTDP-43 pathology. Accumulation of DPRs and the myopathy phenotype could be prevented when 36× G4C2 repeat expression was stopped after 1 week. After 2 weeks of expression, the phenotype could not be reversed, even though DPR levels were reduced. In conclusion, expression of 36× pure G4C2 repeats including 100-bp human flanking regions is sufficient for RAN translation of sense DPRs, and evokes a functional locomotor phenotype. Our inducible mouse model suggests that early diagnosis and treatment are important for C9FTD/ALS patients. This article has an associated First Person interview with the first author of the paper., Summary: Only 36 C9ORF72 repeats are sufficient for RAN translation in a new mouse model for amyotrophic lateral sclerosis and frontotemporal dementia. Reducing toxic dipeptides can prevent but not reverse the phenotype.
- Published
- 2021
13. Neuropathology of FMR1-premutation carriers presenting with dementia and neuropsychiatric symptoms
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Nicolas Charlet-Berguerand, Anke A. Dijkstra, Esmay C van der Toorn, Niels D. Prins, Marianna Bugiani, Wilfred F. A. den Dunnen, Jeroen J.M. Hoozemans, Annemieke J. M. Rozemuller, Renate K. Hukema, Niek A Verwey, Peter K. Todd, Saif N Haify, Rob Willemsen, Pathology, Amsterdam Neuroscience - Neurodegeneration, Neurology, Amsterdam Neuroscience - Cellular & Molecular Mechanisms, Amsterdam Neuroscience - Complex Trait Genetics, Neuroscience Amsterdam, VU University Medical Centre, 1081HV 1117, Amsterdam, Clinical Genetics, Molecular Neuroscience and Ageing Research (MOLAR), Amsterdam UMC - Amsterdam University Medical Center, Erasmus University Medical Center [Rotterdam] (Erasmus MC), VU University Medical Center [Amsterdam], University Medical Center Groningen [Groningen] (UMCG), University of Michigan [Ann Arbor], University of Michigan System, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), and CHARLET BERGUERAND, NICOLAS
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0303 health sciences ,Pathology ,medicine.medical_specialty ,Ataxia ,medicine.diagnostic_test ,business.industry ,[SDV]Life Sciences [q-bio] ,General Engineering ,Neuropathology ,medicine.disease ,FMR1 ,Phenotype ,Hyperintensity ,3. Good health ,[SDV] Life Sciences [q-bio] ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Dementia ,medicine.symptom ,business ,Pathological ,030217 neurology & neurosurgery ,030304 developmental biology ,Genetic testing - Abstract
CGG repeat expansions within the premutation range (55–200) of the FMR1 gene can lead to Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders. These CGG repeats are translated into a toxic polyglycine-containing protein, FMRpolyG. Pathology of Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders comprises FMRpolyG- and p62-positive intranuclear inclusions. Diagnosing a FMR1-premutation carrier remains challenging, as the clinical features overlap with other neurodegenerative diseases. Here, we describe two male cases with Fragile X-associated neuropsychiatric disorders-related symptoms and mild movement disturbances and novel pathological features that can attribute to the variable phenotype. Macroscopically, both donors did not show characteristic white matter lesions on MRI; however, vascular infarcts in cortical- and sub-cortical regions were identified. Immunohistochemistry analyses revealed a high number of FMRpolyG intranuclear inclusions throughout the brain, which were also positive for p62. Importantly, we identified a novel pathological vascular phenotype with inclusions present in pericytes and endothelial cells. Although these results need to be confirmed in more cases, we propose that these vascular lesions in the brain could contribute to the complex symptomology of FMR1-premutation carriers. Overall, our report suggests that Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders may present diverse clinical involvements resembling other types of dementia, and in the absence of genetic testing, FMRpolyG can be used post-mortem to identify premutation carriers.
- Published
- 2021
14. Neuropathology of FMR1‐premutation carriers presenting with dementia and neuropsychiatric symptoms
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Peter K. Todd, Wilfred F. A. den Dunnen, Jeroen J.M. Hoozemans, Nicolas Charlet-Berguerand, Anke A. Dijkstra, Annemieke J.M. Rozemuller, Saif N Haify, Rob Willemsen, Esmay C van der Toorn, Marianna Bugiani, Nicolaas A. Verwey, Renate K. Hukema, and Niels D. Prins
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0303 health sciences ,medicine.medical_specialty ,Epidemiology ,business.industry ,Health Policy ,Neuropathology ,medicine.disease ,FMR1 ,03 medical and health sciences ,Psychiatry and Mental health ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Developmental Neuroscience ,medicine ,Dementia ,Neurology (clinical) ,Geriatrics and Gerontology ,Psychiatry ,business ,030217 neurology & neurosurgery ,030304 developmental biology - Published
- 2020
15. Inducible expression of human C9ORF72 36x G4C2 hexanucleotide repeats is sufficient to cause RAN translation and rapid muscular atrophy in mice
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Alex Maas, Rob F M Verhagen, Rob Willemsen, Renate K. Hukema, Laurens W. J. Bosman, E.C. van der Toorn, and Fréderike W. Riemslagh
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Atrophy ,C9orf72 ,Neurodegeneration ,medicine ,Intron ,Amyotrophic lateral sclerosis ,medicine.symptom ,Biology ,medicine.disease ,Myopathy ,Trinucleotide repeat expansion ,Molecular biology ,Phenotype - Abstract
The hexanucleotide G4C2 repeat expansion in the first intron of the C9ORF72 gene explains the majority of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) cases. Numerous studies have indicated the toxicity of dipeptide repeats (DPRs) which are produced via repeat-associated non-AUG (RAN) translation from the repeat expansion and accumulate in the brain of C9FTD/ALS patients. Mouse models expressing the human C9ORF72 repeat and/or DPRs show variable pathological, functional and behavioral characteristics of FTD and ALS. Here, we report a new Tet-on inducible mouse model that expresses 36x pure G4C2 repeats with 100bp upstream and downstream human flanking regions. Brain specific expression causes the formation of sporadic sense DPRs aggregates upon 6 months dox induction but no apparent neurodegeneration. Expression in the rest of the body evokes abundant sense DPRs in multiple organs, leading to weight loss, neuromuscular junction disruption, myopathy and a locomotor phenotype within the time frame of four weeks. We did not observe any RNA foci or pTDP-43 pathology. Accumulation of DPRs and the myopathy phenotype could be prevented when 36x G4C2 repeat expression was stopped after 1 week. After 2 weeks of expression, the phenotype could not be reversed, even though DPR levels were reduced. In conclusion, expression of 36x pure G4C2 repeats including 100bp human flanking regions is sufficient for RAN translation of sense DPRs and evokes a functional locomotor phenotype. Our inducible mouse model highlights the importance of early diagnosis and treatment for C9FTD/ALS patients.Summary statementOnly 36 C9ORF72 repeats are sufficient for RAN translation in a new mouse model for ALS and FTD. Reducing toxic dipeptides can prevent but not reverse the phenotype.
- Published
- 2020
16. Neuropathology of
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Anke A, Dijkstra, Saif N, Haify, Niek A, Verwey, Niels D, Prins, Esmay C, van der Toorn, Annemieke J M, Rozemuller, Marianna, Bugiani, Wilfred F A, den Dunnen, Peter K, Todd, Nicolas, Charlet-Berguerand, Rob, Willemsen, Renate K, Hukema, and Jeroen J M, Hoozemans
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neuropathology ,FMR1-premutation ,Original Article ,FXTAS ,FXAND ,nuclear inclusions - Abstract
CGG repeat expansions within the premutation range (55–200) of the FMR1 gene can lead to Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders. These CGG repeats are translated into a toxic polyglycine-containing protein, FMRpolyG. Pathology of Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders comprises FMRpolyG- and p62-positive intranuclear inclusions. Diagnosing a FMR1-premutation carrier remains challenging, as the clinical features overlap with other neurodegenerative diseases. Here, we describe two male cases with Fragile X-associated neuropsychiatric disorders-related symptoms and mild movement disturbances and novel pathological features that can attribute to the variable phenotype. Macroscopically, both donors did not show characteristic white matter lesions on MRI; however, vascular infarcts in cortical- and sub-cortical regions were identified. Immunohistochemistry analyses revealed a high number of FMRpolyG intranuclear inclusions throughout the brain, which were also positive for p62. Importantly, we identified a novel pathological vascular phenotype with inclusions present in pericytes and endothelial cells. Although these results need to be confirmed in more cases, we propose that these vascular lesions in the brain could contribute to the complex symptomology of FMR1-premutation carriers. Overall, our report suggests that Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders may present diverse clinical involvements resembling other types of dementia, and in the absence of genetic testing, FMRpolyG can be used post-mortem to identify premutation carriers., FMR1-premutation carriers can present clinically with a range of symptoms, including neuropsychiatric symptoms. Pathologically, the nuclear inclusions are positive for FMRpolyG and in the donors discussed here, also present in the vasculature. This has not been described before and this finding possibly contributes to the complex phenotype., Graphical Abstract Graphical Abstract
- Published
- 2020
17. Reduction of Fmr1 mRNA Levels Rescues Pathological Features in Cortical Neurons in a Model of FXTAS
- Author
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Marielle Jarjat, Enzo Lalli, Sara Castagnola, Maria Capovilla, Sébastien Delhaye, Barbara Bardoni, Frédéric Brau, Mauro Grossi, Thomas Maurin, Renate K. Hukema, Małgorzata Drozd, Rob Willemsen, Clinical Genetics, Institut de pharmacologie moléculaire et cellulaire (IPMC), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), and Erasmus University Medical Center [Rotterdam] (Erasmus MC)
- Subjects
0301 basic medicine ,Untranslated region ,Ataxia ,TIA1 ,[SDV.BC]Life Sciences [q-bio]/Cellular Biology ,Biology ,Article ,dendrtic spine ,03 medical and health sciences ,0302 clinical medicine ,Drug Discovery ,medicine ,Attention deficit hyperactivity disorder ,ROAA ,Aldh4a1/P5CDH ,Parkinsonism ,lcsh:RM1-950 ,Hnrnpll ,[SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology ,Fmr1 mRNA ,medicine.disease ,Phenotype ,FMR1 ,lcsh:Therapeutics. Pharmacology ,030104 developmental biology ,premutation ,[SDV.GEN.GH]Life Sciences [q-bio]/Genetics/Human genetics ,Autism spectrum disorder ,030220 oncology & carcinogenesis ,Tia1 ,Molecular Medicine ,FXTAS ,medicine.symptom ,Neuroscience ,dendritic arborization - Abstract
Fragile X-associated tremor ataxia syndrome (FXTAS) is a rare disorder associated to the presence of the fragile X premutation, a 55–200 CGG repeat expansion in the 5′ UTR of the FMR1 gene. Two main neurological phenotypes have been described in carriers of the CGG premutation: (1) neurodevelopmental disorders characterized by anxiety, attention deficit hyperactivity disorder (ADHD), social deficits, or autism spectrum disorder (ASD); and (2) after 50 years old, the FXTAS phenotype. This neurodegenerative disorder is characterized by ataxia and a form of parkinsonism. The molecular pathology of this disorder is characterized by the presence of elevated levels of Fragile X Mental Retardation 1 (FMR1) mRNA, presence of a repeat-associated non-AUG (RAN) translated peptide, and FMR1 mRNA-containing nuclear inclusions. Whereas in the past FXTAS was mainly considered as a late-onset disorder, some phenotypes of patients and altered learning and memory behavior of a mouse model of FXTAS suggested that this disorder involves neurodevelopment. To better understand the physiopathological role of the increased levels of Fmr1 mRNA during neuronal differentiation, we used a small interfering RNA (siRNA) approach to reduce the abundance of this mRNA in cultured cortical neurons from the FXTAS mouse model. Morphological alterations of neurons were rescued by this approach. This cellular phenotype is associated to differentially expressed proteins that we identified by mass spectrometry analysis. Interestingly, phenotype rescue is also associated to the rescue of the abundance of 29 proteins that are involved in various pathways, which represent putative targets for early therapeutic approaches. Keywords: FXTAS, premutation, Fmr1 mRNA, dendritic arborization, Tia1, ROAA, Hnrnpll, Aldh4a1/P5CDH, dendrtic spine
- Published
- 2019
18. Astroglial-targeted expression of the fragile X CGG repeat premutation in mice yields RAN translation, motor deficits and possible evidence for cell-to-cell propagation of FXTAS pathology
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Kyoungmi Kim, Michael R. Hunsaker, Lies Anne Severijnen, Saif N Haify, Rob Willemsen, Albert R. La Spada, H. Jürgen Wenzel, Paul J. Hagerman, Christopher Raske, Bryce L. Sopher, Robert F. Berman, Karl D Murray, Renate K. Hukema, Jared J. Schwartzer, and Clinical Genetics
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0301 basic medicine ,Male ,Pathology ,Gene Expression ,Cell Communication ,Neurodegenerative ,Inbred C57BL ,Transgenic ,lcsh:RC346-429 ,Fragile X Mental Retardation Protein ,Mice ,0302 clinical medicine ,Tremor ,Non-cell-autonomous ,Neocortex ,biology ,Neurodegeneration ,Fragile X premutation ,Motor Skills Disorders ,medicine.anatomical_structure ,Neurological ,FMRpolyG ,medicine.symptom ,Astrocyte ,medicine.medical_specialty ,Ataxia ,Intellectual and Developmental Disabilities (IDD) ,Clinical Sciences ,Mice, Transgenic ,Neuropathology ,Pathology and Forensic Medicine ,Mouse model ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Rare Diseases ,RAN translation ,Glia ,Genetics ,medicine ,Animals ,lcsh:Neurology. Diseases of the nervous system ,Electron microscopy of inclusions ,Base Sequence ,Research ,Neurosciences ,medicine.disease ,FMR1 ,Brain Disorders ,Mice, Inbred C57BL ,030104 developmental biology ,nervous system ,Astrocytes ,Fragile X Syndrome ,biology.protein ,Biochemistry and Cell Biology ,Neurology (clinical) ,FXTAS ,NeuN ,Trinucleotide repeat expansion ,Trinucleotide Repeat Expansion ,030217 neurology & neurosurgery - Abstract
The fragile X premutation is a CGG trinucleotide repeat expansion between 55 and 200 repeats in the 5′-untranslated region of the fragile X mental retardation 1 (FMR1) gene. Human carriers of the premutation allele are at risk of developing the late-onset neurodegenerative disorder, fragile X-associated tremor/ataxia syndrome (FXTAS). Characteristic neuropathology associated with FXTAS includes intranuclear inclusions in neurons and astroglia. Previous studies recapitulated these histopathological features in neurons in a knock-in mouse model, but without significant astroglial pathology. To determine the role of astroglia in FXTAS, we generated a transgenic mouse line (Gfa2-CGG99-eGFP) that selectively expresses a 99-CGG repeat expansion linked to an enhanced green fluorescent protein (eGFP) reporter in astroglia throughout the brain, including cerebellar Bergmann glia. Behaviorally these mice displayed impaired motor performance on the ladder-rung test, but paradoxically better performance on the rotarod. Immunocytochemical analysis revealed that CGG99-eGFP co-localized with GFAP and S-100ß, but not with NeuN, Iba1, or MBP, indicating that CGG99-eGFP expression is specific to astroglia. Ubiquitin-positive intranuclear inclusions were found in eGFP-expressing glia throughout the brain. In addition, intracytoplasmic ubiquitin-positive inclusions were found outside the nucleus in distal astrocyte processes. Intriguingly, intranuclear inclusions, in the absence of eGFP mRNA and eGFP fluorescence, were present in neurons of the hypothalamus and neocortex. Furthermore, intranuclear inclusions in both neurons and astrocytes displayed immunofluorescent labeling for the polyglycine peptide FMRpolyG, implicating FMRpolyG in the pathology found in Gfa2-CGG99 mice. Considered together, these results show that Gfa2-CGG99 expression in mice is sufficient to induce key features of FXTAS pathology, including formation of intranuclear inclusions, translation of FMRpolyG, and deficits in motor function. Electronic supplementary material The online version of this article (10.1186/s40478-019-0677-7) contains supplementary material, which is available to authorized users.
- Published
- 2019
19. Potential pathogenic mechanisms underlying Fragile X Tremor Ataxia Syndrome: RAN translation and/or RNA gain-of-function?
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Chantal Sellier, Renate K. Hukema, Rob Willemsen, Manon Boivin, Centre for Integrative Biology - CBI (Inserm U964 - CNRS UMR7104 - IGBMC), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Erasmus University Medical Center [Rotterdam] (Erasmus MC), Dieterle, Stéphane, and Clinical Genetics
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0301 basic medicine ,MESH: Ataxia ,[SDV]Life Sciences [q-bio] ,MESH: Neurons ,MESH: Tremor ,Fragile X Mental Retardation Protein ,0302 clinical medicine ,Tremor ,MESH: Trinucleotide Repeat Expansion ,MESH: Animals ,Genetics (clinical) ,Neurons ,Fragile X Tremor/Ataxia Syndrome ,Brain ,General Medicine ,3. Good health ,Antisense RNA ,[SDV] Life Sciences [q-bio] ,Gain of Function Mutation ,Intention tremor ,medicine.symptom ,MESH: Fragile X Syndrome ,congenital, hereditary, and neonatal diseases and abnormalities ,Ataxia ,MESH: Ubiquitin ,Biology ,MESH: Fragile X Mental Retardation Protein ,03 medical and health sciences ,MESH: Brain ,Atrophy ,RAN translation ,Genetics ,medicine ,Animals ,Humans ,MESH: Gain of Function Mutation ,MESH: Humans ,Ubiquitin ,RNA ,medicine.disease ,FMR1 ,nervous system diseases ,MESH: Astrocytes ,Disease Models, Animal ,030104 developmental biology ,Astrocytes ,Fragile X Syndrome ,Gait Ataxia ,FXTAS ,MESH: Disease Models, Animal ,Trinucleotide Repeat Expansion ,RNA gain-of-function ,Neuroscience ,Microsatellite expansion ,030217 neurology & neurosurgery - Abstract
International audience; Fragile X-associated tremor/ataxia syndrome (FXTAS) is an inherited neurodegenerative disease caused by an expansion of 55-200 CGG repeats located in the FMR1 gene. The main clinical and neuropathological features of FXTAS are progressive intention tremor and gait ataxia associated with brain atrophy, neuronal cell loss and presence of ubiquitin-positive intranuclear inclusions in both neurons and astrocytes. At the molecular level, FXTAS is characterized by increased expression of FMR1 sense and antisense RNA containing expanded CGG or GGC repeats, respectively. Here, we discuss the putative molecular mechanisms underlying FXTAS and notably recent reports that expanded CGG and GGC repeats may be pathogenic through RAN translation into toxic proteins.
- Published
- 2018
20. Presence of inclusions positive for polyglycine containing protein, FMRpolyG, indicates that repeat-associated non-AUG translation plays a role in fragile X-associated primary ovarian insufficiency
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Marla Gearing, Nicolas Charlet-Berguerand, E. A W F M Severijnen, Rob Willemsen, Jenny A. Visser, Ronald A.M. Buijsen, Piet Kramer, Stephanie L. Sherman, Robert F. Berman, Renate K. Hukema, Clinical Genetics, and Internal Medicine
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Male ,0301 basic medicine ,inclusions ,Intranuclear Inclusion Bodies ,ovarian failure ,Hypothalamic–pituitary–gonadal axis ,Primary Ovarian Insufficiency ,Inbred C57BL ,Medical and Health Sciences ,Mice ,Fragile X Mental Retardation Protein ,Tremor ,2.1 Biological and endogenous factors ,Aetiology ,FXPOI ,media_common ,Rehabilitation ,Obstetrics and Gynecology ,Middle Aged ,HPG-axis ,medicine.anatomical_structure ,Studies in Human Society ,FMRpolyG ,Immunohistochemistry ,Female ,trinucleotide repeat expansion ,Adult ,medicine.medical_specialty ,Intellectual and Developmental Disabilities (IDD) ,media_common.quotation_subject ,Ovary ,Biology ,03 medical and health sciences ,Follicle ,Rare Diseases ,RAN translation ,Internal medicine ,Genetics ,medicine ,Animals ,Humans ,Ovarian follicle ,Obstetrics & Reproductive Medicine ,Ovulation ,Aged ,Animal ,Neurosciences ,CGG-repeat ,Original Articles ,Antral follicle ,FMR1 ,Brain Disorders ,Mice, Inbred C57BL ,Disease Models, Animal ,030104 developmental biology ,Endocrinology ,Reproductive Medicine ,Fragile X Syndrome ,Disease Models ,Mutation ,Ataxia ,FXTAS ,Trinucleotide Repeat Expansion ,Peptides ,FMR1 premutation - Abstract
STUDY QUESTION Does repeat-associated non-AUG (RAN) translation play a role in fragile X-associated primary ovarian insufficiency (FXPOI), leading to the presence of polyglycine containing protein (FMRpolyG)-positive inclusions in ovarian tissue? SUMMARY ANSWER Ovaries of a woman with FXPOI and of an Fmr1 premutation (PM) mouse model (exCGG-KI) contain intranuclear inclusions that stain positive for both FMRpolyG and ubiquitin. WHAT IS KNOWN ALREADY Women who carry the FMR1 PM are at 20-fold increased risk to develop primary ovarian insufficiency (FXPOI). A toxic RNA gain-of-function has been suggested as the underlying mechanism since the PM results in increased levels of mRNA containing an expanded repeat, but reduced protein levels of fragile X mental retardation protein (FMRP). Recently, RAN translation has been shown to occur from FMR1 mRNA that contains PM repeat expansions, leading to FMRpolyG inclusions in brain and non-CNS tissues of fragile X-associated tremor/ataxia syndrome (FXTAS) patients. STUDY DESIGN, SIZE, DURATION Ovaries of a woman with FXPOI and women without PM (controls), and ovaries from wild-type and exCGG-KI mice were analyzed by immunohistochemistry for the presence of inclusions that stained for ubiquitin and FMRpolyG . The ovaries from wild-type and exCGG-KI mice were further characterized for the number of follicles, Fmr1 mRNA levels and FMRP protein expression. The presence of inclusions was also analyzed in pituitaries of a man with FXTAS and the exCGG-KI mice. PARTICIPANTS/MATERIALS, SETTING, METHODS Human ovaries from a woman with FXPOI and two control subjects and pituitaries from a man with FXTAS and a control subjects were fixed in 4% formalin. Ovaries and pituitaries of wild-type and exCGG mice were fixed in Bouin's fluid or 4% paraformaldehyde. Immunohistochemistry was performed on the human and mouse samples using FMRpolyG, ubiquitin and Fmrp antibodies. Fmr1 mRNA and protein expression were determined in mouse ovaries by quantitative RT-PCR and Western blot analysis. Follicle numbers in mouse ovaries were determined in serial sections by microscopy. MAIN RESULTS AND THE ROLE OF CHANCE FMRpolyG-positive inclusions were present in ovarian stromal cells of a woman with FXPOI but not in the ovaries of control subjects. The FMRpolyG-positive inclusions colocalized with ubiquitin-positive inclusions. Similar inclusions were also observed in the pituitary of a man with FXTAS but not in control subjects. Similarly, ovaries of 40-week-old exCGG-KI mice, but not wild-type mice, contained numerous inclusions in the stromal cells that stained for both FMRpolyG- and ubiquitin, while the ovaries of 20-week-old exCGG-KI contained fewer inclusions. At 40 weeks ovarian Fmr1 mRNA expression was increased by 5-fold in exCGG-KI mice compared with wild-type mice, while Fmrp expression was reduced by 2-fold. With respect to ovarian function in exCGG-KI mice: (i) although the number of healthy growing follicles did not differ between wild-type and exCGG-KI mice, the number of atretic large antral follicles was increased by nearly 9-fold in 40-week old exCGG-KI mice (P < 0.001); (ii) at 40 weeks of age only 50% of exCGG-KI mice had recent ovulations compared with 89% in wild-type mice (P = 0.07) and (iii) those exCGG-KI mice with recent ovulations tended to have a reduced number of fresh corpora lutea (4.8 ± 1.74 versus 8.50 ± 0.98, exCGG-KI versus wild-type mice, respectively, P = 0.07). LIMITATIONS, REASONS FOR CAUTION Although FMRpolyG-positive inclusions were detected in ovaries of both a woman with FXPOI and a mouse model of the FMR1 PM, we only analyzed one ovary from a FXPOI subject. Caution is needed to extrapolate these results to all women with the FMR1 PM. Furthermore, the functional consequence of FMRpolyG-positive inclusions in the ovaries for reproduction remains to be determined. WIDER IMPLICATIONS OF THE FINDINGS Our results suggest that a dysfunctional hypothalamic-pituitary-gonadal-axis may contribute to FXPOI in FMR1 PM carriers. STUDY FUNDING/COMPETING INTERESTS This study was supported by grants from NFXF, ZonMW, the Netherlands Brain Foundation and NIH. The authors have no conflict of interest to declare.
- Published
- 2015
21. An integrative study on ribonucleoprotein condensates identifies scaffolding RNAs and reveals a new player in Fragile X-associated Tremor/Ataxia Syndrome
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Mariona Gelabert-Baldrich, Nieves Lorenzo-Gotor, Ellen Gelpi, Fernando Cid-Samper, Gian Gaetano Tartaglia, Lies-Anne Severijnen, Teresa Botta-Orfila, Benjamin Lang, Renate K. Hukema, Benedetta Bolognesi, and Riccardo Delli Ponti
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Untranslated region ,0303 health sciences ,Fragile X Tremor/Ataxia Syndrome ,Chemistry ,RNA ,FMR1 ,Ribosome assembly ,Protein–protein interaction ,Cell biology ,03 medical and health sciences ,0302 clinical medicine ,RNA splicing ,030217 neurology & neurosurgery ,030304 developmental biology ,Ribonucleoprotein - Abstract
Ribonucleoprotein (RNP) granules are dense aggregations composed of RNA-binding proteins (RBPs) and a part of the transcriptome that is still uncharacterized. We performed a large-scale study of interaction networks and discovered that RBPs phase-separating in RNP granules share specific RNA partners with high structural content, long untranslated regions (UTRs) and nucleotide repeat expansions. Our analysis suggests that RNAs can promote formation of RNP granules by acting as scaffolds for protein assembly. To experimentally validate our findings, we investigated the scaffolding ability of CGG repeats contained in the 5’ UTR of FMR1 transcript implicated in Fragile X-associated Tremor / Ataxia Syndrome (FXTAS). Using a novel high-throughput approach we identified RBPs recruited by FMR1 5’ UTRs of different lengths. We employed human primary tissues as well as primate and mouse models of FXTAS to characterize protein sequestration in FMR1 aggregates and focused on a previously unreported partner, TRA2A, which induces impairment of splicing in genes linked to mental retardation and intellectual disability. SIGNIFICANCE Proteins and RNAs phase-separate into granules under physiological (ribosome assembly and shuttling through neurons) and pathological (Amyotrophic Lateral Sclerosis and Fragile X Tremor/Ataxia Syndrome) conditions. We report here that granule-forming proteins share more RNA targets than other proteins and form a dense network of interactions. RNAs interacting with granule-forming proteins have longer UTRs, are more structured and contain nucleotide repeats. Our study suggests that specific RNAs can act as the ‘glue’ of ribonucleoprotein assemblies. To experimentally validate the results of our analysis, we investigated how nucleotide repeats contained in the 5’ UTR of FMR1 are able to sequester proteins in intranuclear inclusions. We predicted protein interactions in silico, confirmed them in vitro and further characterized the ribonucleoprotein aggregates in vivo.
- Published
- 2018
22. Paradoxical effect of baclofen on social behavior in the fragile X syndrome mouse model
- Author
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Celine de Esch, Andreea S. Pop, Renate K. Hukema, Israa A. Jaafar, Ronald A.M. Buijsen, Shimriet Zeidler, Helen de Boer, Rob Willemsen, Ingeborg Nieuwenhuizen-Bakker, and Clinical Genetics
- Subjects
Male ,0301 basic medicine ,Baclofen ,congenital, hereditary, and neonatal diseases and abnormalities ,Neuropsychological Tests ,Inhibitory postsynaptic potential ,Fragile X Mental Retardation Protein ,Mice ,03 medical and health sciences ,Behavioral Neuroscience ,chemistry.chemical_compound ,0302 clinical medicine ,Postsynaptic potential ,medicine ,Animals ,RNA, Messenger ,Social Behavior ,Mice, Knockout ,business.industry ,medicine.disease ,FMR1 ,Mice, Inbred C57BL ,Fragile X syndrome ,Disease Models, Animal ,030104 developmental biology ,nervous system ,chemistry ,Fragile X Syndrome ,GABA-B Receptor Agonists ,Synapses ,Synaptic plasticity ,Excitatory postsynaptic potential ,Autism ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
textabstractIntroduction: Fragile X syndrome (FXS) is a common monogenetic cause of intellectual disability, autism spectrum features, and a broad range of other psychiatric and medical problems. FXS is caused by the lack of the fragile X mental retardation protein (FMRP), a translational regulator of specific mRNAs at the postsynaptic compartment. The absence of FMRP leads to aberrant synaptic plasticity, which is believed to be caused by an imbalance in excitatory and inhibitory network functioning of the synapse. Evidence from studies in mice demonstrates that GABA, the major inhibitory neurotransmitter in the brain, and its receptors, is involved in the pathogenesis of FXS. Moreover, several FXS phenotypes, including social behavior deficits, could be corrected in Fmr1 KO mice after acute treatment with GABAB agonists. Methods: As FXS would probably require a lifelong treatment, we investigated the effect of chronic treatment with the GABAB agonist baclofen on social behavior in Fmr1 KO mice on two behavioral paradigms for social behavior: the automated tube test and the three-chamber sociability test. Results: Unexpectedly, chronic baclofen treatment resulted in worsening of the FXS phenotypes in these behavior tests. Strikingly, baclofen treatment also affected wild-type animals in both behavioral tests, inducing a phenotype similar to that of untreated Fmr1 KO mice. Conclusion: Altogether, the disappointing results of recent clinical trials with the R-baclofen enantiomer arbaclofen and our current results indicate that baclofen should be reconsidered and further evaluated before its application in targeted treatment for FXS.
- Published
- 2018
23. An Integrative Study of Ribonucleoprotein Condensates Reveals a Biomarker for Fragile X-Associated Tremor/Ataxia Syndrome
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Benjamin Lang, Gian Gaetano Tartaglia, Mariona Gelabert-Baldrich, Riccardo Delli Ponti, Nieves Lorenzo-Gotor, Teresa Botta-Orfila, Lies-Anne Severijnen, Ellen Gelpi, Benedetta Bolognesi, Fernando Cid-Samper, and Renate K. Hukema
- Subjects
business.industry ,Cancer research ,medicine ,Biomarker (medicine) ,medicine.disease ,business ,Fragile X-associated tremor/ataxia syndrome ,Ribonucleoprotein - Published
- 2018
24. Combination Therapy in Fragile X Syndrome; Possibilities and Pitfalls Illustrated by Targeting the mGluR5 and GABA Pathway Simultaneously
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Helen de Boer, Shimriet Zeidler, Rob Willemsen, Renate K. Hukema, and Clinical Genetics
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0301 basic medicine ,congenital, hereditary, and neonatal diseases and abnormalities ,Fmr1 KO mouse ,autism ,Biology ,Inhibitory postsynaptic potential ,bumetanide ,lcsh:RC321-571 ,Synapse ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,GABA ,0302 clinical medicine ,medicine ,Molecular Biology ,FMR1 ,mGluR5 ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Metabotropic glutamate receptor 5 ,medicine.disease ,Fragile X syndrome ,030104 developmental biology ,Synaptic plasticity ,Perspective ,automated tube test ,Autism ,GABAergic ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Fragile X syndrome (FXS) is the most common monogenetic cause of intellectual disability and autism. The disorder is characterized by altered synaptic plasticity in the brain. Synaptic plasticity is tightly regulated by a complex balance of different synaptic pathways. In FXS, various synaptic pathways are disrupted, including the excitatory metabotropic glutamate receptor 5 (mGluR5) and the inhibitory γ-aminobutyric acid (GABA) pathways. Targeting each of these pathways individually, has demonstrated beneficial effects in animal models, but not in patients with FXS. This lack of translation might be due to oversimplification of the disease mechanisms when targeting only one affected pathway, in spite of the complexity of the many pathways implicated in FXS. In this report we outline the hypothesis that targeting more than one pathway simultaneously, a combination therapy, might improve treatment effects in FXS. In addition, we present a glance of the first results of chronic combination therapy on social behavior in Fmr1 KO mice. In contrast to what we expected, targeting both the mGluR5 and the GABAergic pathways simultaneously did not result in a synergistic effect, but in a slight worsening of the social behavior phenotype. This does implicate that both pathways are interconnected and important for social behavior. Our results underline the tremendous fine-tuning that is needed to reach the excitatory-inhibitory balance in the synapse in relation to social behavior. We believe that alternative strategies focused on combination therapy should be further explored, including targeting pathways in different cellular compartments or cell-types.
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- 2017
25. The quest for targeted therapy in fragile X syndrome
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Shimriet Zeidler, Renate K. Hukema, Rob Willemsen, and Clinical Genetics
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congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_treatment ,Clinical Biochemistry ,Bioinformatics ,Targeted therapy ,Mice ,Drug Discovery ,Intellectual disability ,medicine ,Animals ,Humans ,Molecular Targeted Therapy ,Functional studies ,Pharmacology ,Genetics ,business.industry ,Publication bias ,medicine.disease ,FMR1 ,Fragile X syndrome ,Clinical trial ,Disease Models, Animal ,Phenotype ,Drug Design ,Fragile X Syndrome ,Molecular Medicine ,Animal studies ,business - Abstract
Fragile X syndrome (FXS) is the most common, monogenetic cause of intellectual disability and autism-spectrum disorders. Although there is no effective therapy, greater understanding of disturbed neuronal pathways has introduced options for targeted therapy. But whereas many FXS phenotypes were improved in preclinical studies with drugs targeting these pathways in the FXS mouse model, attempts to translate these animal-model success stories into treatment of patients in clinical trials have been extremely disappointing. Complicating factors, particularly in animal studies, include mouse inbred strains, variability in functional studies between laboratories, publication bias and lack of reliable and objective primary outcome measures in both mice and patients. Possibly most important, however, is one factor that has been little explored: the complexity of the molecular imbalance in FXS and the need to simultaneously target several different disturbed pathways and different cellular compartments. New, well-conceived animal studies should generate more productive approaches in the quest for targeted therapy for FXS.
- Published
- 2015
26. Selective rescue of heightened anxiety but not gait ataxia in a premutation 90CGG mouse model of Fragile X-associated tremor/ataxia syndrome
- Author
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Emre Kul, Hoanna Castro, Lies-Anne Severijnen, Oliver Stork, Renate K. Hukema, Mónica Santos, Ronald A.M. Buijsen, Rob Willemsen, and Clinical Genetics
- Subjects
0301 basic medicine ,Gait Ataxia ,Cerebellum ,Ataxia ,Cerebellar Ataxia ,Intranuclear Inclusion Bodies ,Context (language use) ,Neuropathology ,Biology ,Anxiety ,03 medical and health sciences ,Fragile X Mental Retardation Protein ,Mice ,0302 clinical medicine ,Tremor ,Genetics ,medicine ,Animals ,Molecular Biology ,Gait ,Genetics (clinical) ,Neurons ,Movement Disorders ,Brain ,General Medicine ,Articles ,medicine.disease ,FMR1 ,Motor coordination ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Fragile X Syndrome ,medicine.symptom ,Cognition Disorders ,Trinucleotide Repeat Expansion ,Neuroscience ,030217 neurology & neurosurgery ,Fragile X-associated tremor/ataxia syndrome - Abstract
A CGG-repeat expansion in the premutation range in the Fragile X mental retardation 1 gene (FMR1) has been identified as the genetic cause of Fragile X-associated tremor/ataxia syndrome (FXTAS), a late-onset neurodegenerative disorder that manifests with action tremor, gait ataxia and cognitive impairments. In this study, we used a bigenic mouse model, in which expression of a 90CGG premutation tract is activated in neural cells upon doxycycline administration-P90CGG mouse model. We, here, demonstrate the behavioural manifestation of clinically relevant features of FXTAS patients and premutation carrier individuals in this inducible mouse model. P90CGG mice display heightened anxiety, deficits in motor coordination and impaired gait and represent the first FXTAS model that exhibits an ataxia phenotype as observed in patients. The behavioural phenotype is accompanied by the formation of ubiquitin/FMRpolyglycine-positive intranuclear inclusions, as another hallmark of FXTAS, in the cerebellum, hippocampus and amygdala. Strikingly, upon cessation of transgene induction the anxiety phenotype of mice recovers along with a reduction of intranuclear inclusions in dentate gyrus and amygdala. In contrast, motor function deteriorates further and no reduction in intranuclear inclusions can be observed in the cerebellum. Our data thus demonstrate that expression of a 90CGG premutation expansion outside of the FMR1 context is sufficient to evoke an FXTAS-like behavioural phenotype. Brain region-specific neuropathology and (partial) behavioural reversibility make the inducible P90CGG a valuable mouse model for testing pathogenic mechanisms and therapeutic intervention methods.
- Published
- 2017
27. Translation of Expanded CGG Repeats into FMRpolyG Is Pathogenic and May Contribute to Fragile X Tremor Ataxia Syndrome
- Author
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Marie-Christine Birling, Chantal Sellier, Frank Ruffenach, Cécile Martinat, Marie Wattenhofer-Donzé, Stéphane Viville, Ronald A.M. Buijsen, Mustapha Oulad-Abdelghani, Hamid Meziane, Peter K. Todd, Alexandre Vincent, Guillaume Pavlovic, Pascal Eberling, Hugues Jacobs, Verónica Martínez-Cerdeño, Flora Tassone, Marie-France Champy, Laura Jung, Fang He, Nicolas Charlet-Berguerand, Philippe Tropel, Mathieu Anheim, Angeline Gaucherot, Tania Sorg, Renate K. Hukema, Mathilde Joint, Rob Willemsen, Sam Natla, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Erasmus University Medical Center [Rotterdam] (Erasmus MC), University of Michigan [Ann Arbor], University of Michigan System, Institut Clinique de la Souris (ICS), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Strasbourg (UNISTRA), Hôpital de Hautepierre [Strasbourg], University of California [Davis] (UC Davis), University of California, Laboratoire de Diagnostic Génétique [CHU Strasbourg], Université de Strasbourg (UNISTRA)-CHU Strasbourg, Nouvel Hôpital Civil de Strasbourg, Institut de Parasitologie et de Pathologie Tropicale (IPPTS), Université de Strasbourg (UNISTRA), Université d'Évry-Val-d'Essonne (UEVE), Institut des cellules souches pour le traitement et l'étude des maladies monogéniques (I-STEM), Université d'Évry-Val-d'Essonne (UEVE)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris-Saclay-Généthon, Association française contre les myopathies (AFM-Téléthon), Centre for Integrative Biology - CBI (Inserm U964 - CNRS UMR7104 - IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), French National Infrastructure for Mouse Phenogenomics (PHENOMIN), CHU Strasbourg, University of California (UC), Dieterle, Stéphane, and Clinical Genetics
- Subjects
Male ,0301 basic medicine ,Untranslated region ,MESH: Ataxia ,[SDV]Life Sciences [q-bio] ,MESH: Tremor ,MESH: Nuclear Lamina ,Pathogenesis ,Fragile X Mental Retardation Protein ,Mice ,[SCCO]Cognitive science ,Tremor ,MESH: Trinucleotide Repeat Expansion ,MESH: Animals ,Induced pluripotent stem cell ,ComputingMilieux_MISCELLANEOUS ,Genetics ,Fragile X Tremor/Ataxia Syndrome ,MESH: Peptides ,MESH: Real-Time Polymerase Chain Reaction ,General Neuroscience ,neurodegeneration ,Brain ,Translation (biology) ,3. Good health ,DNA-Binding Proteins ,[SDV] Life Sciences [q-bio] ,MESH: Protein Biosynthesis ,Nuclear lamina ,MESH: Membrane Proteins ,MESH: Fragile X Syndrome ,medicine.symptom ,congenital, hereditary, and neonatal diseases and abnormalities ,near-cognate codon ,Ataxia ,MESH: Mice, Transgenic ,Neuroscience(all) ,Mice, Transgenic ,Biology ,Real-Time Polymerase Chain Reaction ,MESH: Fragile X Mental Retardation Protein ,Article ,MESH: Brain ,03 medical and health sciences ,RAN translation ,medicine ,Animals ,Humans ,RNA, Messenger ,MESH: Mice ,MESH: RNA, Messenger ,Nuclear Lamina ,MESH: Humans ,Membrane Proteins ,RNA ,[SCCO] Cognitive science ,microsatellite expansion ,MESH: Male ,nervous system diseases ,030104 developmental biology ,Fragile X Syndrome ,Protein Biosynthesis ,Peptides ,Trinucleotide Repeat Expansion ,MESH: DNA-Binding Proteins - Abstract
Summary Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder caused by a limited expansion of CGG repeats in the 5′ UTR of FMR1. Two mechanisms are proposed to cause FXTAS: RNA gain-of-function, where CGG RNA sequesters specific proteins, and translation of CGG repeats into a polyglycine-containing protein, FMRpolyG. Here we developed transgenic mice expressing CGG repeat RNA with or without FMRpolyG. Expression of FMRpolyG is pathogenic, while the sole expression of CGG RNA is not. FMRpolyG interacts with the nuclear lamina protein LAP2β and disorganizes the nuclear lamina architecture in neurons differentiated from FXTAS iPS cells. Finally, expression of LAP2β rescues neuronal death induced by FMRpolyG. Overall, these results suggest that translation of expanded CGG repeats into FMRpolyG alters nuclear lamina architecture and drives pathogenesis in FXTAS., Highlights • CGG repeats in the 5′ UTR of FMR1 are translated through initiation to an ACG codon • Translation of CGG repeats in the polyglycine protein, FMRpolyG, is toxic in mice • FMRpolyG binds and disrupts protein of the nuclear lamina, Sellier et al. show that translation of expanded CGG repeats located in the 5′ UTR of the FMR1 gene require an upstream ACG near-cognate initiation codon. Translation of CGG repeats into a short polyglycine-containing protein, FMRpolyG, is pathogenic in mouse models.
- Published
- 2017
28. Refining the spectrum of neuronal intranuclear inclusion disease : A case report
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Shami Melhem, Lies Anne Severijnen, John C. van Swieten, Meike W. Vernooij, Harro Seelaar, Renate K. Hukema, Manuela Neumann, Chiara Cupidi, Anke A. Dijkstra, Annemieke J. M. Rozemuller, Pathology, Amsterdam Neuroscience - Neurodegeneration, Neurology, Radiology & Nuclear Medicine, and Clinical Genetics
- Subjects
Pathology ,Intranuclear Inclusion Bodies ,diagnostic imaging [Neurodegenerative Diseases] ,P62 ,Hippocampus ,Neuronal intranuclear inclusion disease ,Myelin ,Nerve Fibers ,0302 clinical medicine ,pathology [Brain] ,Intranuclear inclusions ,Myelin Sheath ,Cerebral Cortex ,Temporal cortex ,Muscle Weakness ,Parkinsonism ,pathology [Neurodegenerative Diseases] ,Leukoaraiosis ,Brain ,Neurodegenerative Diseases ,pathology [Nerve Fibers] ,General Medicine ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Neurology ,pathology [Leukoaraiosis] ,Neuroglia ,Female ,psychology [Cognitive Dysfunction] ,Autopsy ,medicine.symptom ,Optineurin ,medicine.medical_specialty ,Ataxia ,Clinical Neurology ,Pathology and Forensic Medicine ,White matter ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,pathology [Myelin Sheath] ,medicine ,Humans ,Cognitive Dysfunction ,ddc:610 ,diagnostic imaging [Brain] ,pathology [Muscle Weakness] ,Aged ,pathology [Neuroglia] ,business.industry ,pathology [Intranuclear Inclusion Bodies] ,medicine.disease ,Diffusion Magnetic Resonance Imaging ,pathology [Cerebral Cortex] ,Dementia ,psychology [Neurodegenerative Diseases] ,Neurology (clinical) ,Atrophy ,business ,030217 neurology & neurosurgery - Abstract
Neuronal intranuclear inclusion disease (NIID) is a rare heterogeneous progressive neurodegenerative disease characterized by the presence of eosinophilic hyaline intranuclear inclusions in neuronal and glial cells of the CNS, peripheral cells of the autonomic nervous system, visceral organs and skin. The clinical presentation is broadly heterogeneous and includes limb weakness, dementia, seizures, ataxia, and parkinsonism. High-intensity signal in the corticomedullary junction on brain MRI is a characteristic finding in NIID. We describe a 65-year-old patient presenting with mild cognitive impairment, evolving in dementia with behavioral disturbances and parkinsonism. Brain MRI showed mild global cortical atrophy, more pronounced in the cingulate and temporal cortex and mild leukoaraiosis, but no high-intensity signal in corticomedullary junction on diffusion weighted imaging. Neuropathological examination showed p62- and optineurin-positive neuronal intranuclear inclusions in the hippocampus and in some subcortical structures. Glial cells did not present any intranuclear inclusions, and no spongiotic changes proximal to the U-fibers or diffuse myelin pallor were disclosed in the white matter. We report on a case with pathological features of NIID showing different neuroimaging and pathological findings. We noted an absence of typical MRI abnormalities, lack of intranuclear inclusions in glial cells, and prominent involvement of hippocampal neurons, refining the clinico-pathological spectrum of the disease.
- Published
- 2019
29. Fragile X‐associated tremor/ataxia syndrome: Regional decrease of mitochondrial DNA copy number relates to clinical manifestations
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Ellen Gelpi, Montserrat Milà, Irene Madrigal, Renate K. Hukema, Petar Podlesniy, Ramon Trullas, Laia Rodriguez-Revenga, Maria Isabel Alvarez-Mora, Javier Pagonabarraga, Generalitat de Catalunya, Agencia Estatal de Investigación (España), Centro Investigación Biomédica en Red Enfermedades Neurodegenerativas (España), Instituto de Salud Carlos III, Ministerio de Ciencia, Innovación y Universidades (España), and Clinical Genetics
- Subjects
Male ,0301 basic medicine ,Mitochondrial DNA ,Ataxia ,mtDNA copy number ,DNA Copy Number Variations ,ddPCR ,Biology ,DNA, Mitochondrial ,Fragile X Mental Retardation Protein ,Mice ,03 medical and health sciences ,Behavioral Neuroscience ,0302 clinical medicine ,Genetics ,medicine ,Animals ,Humans ,Cells, Cultured ,Aged ,Aged, 80 and over ,Temporal cortex ,Neurodegeneration ,neurodegeneration ,Brain ,Human brain ,medicine.disease ,FMR1 ,030104 developmental biology ,medicine.anatomical_structure ,Dentate nucleus ,Neurology ,Fragile X Syndrome ,Female ,FXTAS ,medicine.symptom ,FMR1 premutation ,030217 neurology & neurosurgery ,Fragile X-associated tremor/ataxia syndrome - Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder that appears in at least one-third of adult carriers of a premutation (55-200 CGG repeats) in the fragile X mental retardation 1 (FMR1) gene. Several studies have shown that mitochondrial dysfunction may play a central role in aging and also in neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease as well as in FXTAS. It has been recently proposed that mtDNA copy number, measured by the number of mitochondrial genomes per nuclear genome (diploid), could be a useful biomarker of mitochondrial dysfunction. In order to elucidate the role of mtDNA variation in the pathogenesis of FXTAS, mtDNA copy number was quantified by digital droplet Polymerase chain reaction. In human brain samples, mtDNA levels were measured in the cerebellar vermis, dentate nucleus, parietal and temporal cortex, thalamus, caudate nucleus and hippocampus from a female FXTAS patient, a FMR1 premutation male carrier without FXTAS and from three male controls. The mtDNA copy number was further analyzed using this technology in dermal fibroblasts primary cultures derived from three FXTAS patients and three controls as well as in cortex and cerebellum of a CGG knock in FXTAS mice model. Finally, qPCR was carried out in human blood samples. Results indicate reduced mtDNA copy number in the specific brain region associated with disease progression in FXTAS patients, providing new insights into the role of mitochondrial dysfunction in the pathogenesis of FXTAS., Agència de Gestió d'Ajuts Universitaris i de Recerca, Grant/Award Numbers: 2014SGR603, 2017SGR1134; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Grant/Award Number: PI2016/06; Instituto de Salud Carlos III, Grant/Award Numbers: PI12/00879, PI17/01067; Ministerio de Ciencia e Innovación, Grant/Award Number: SAF2017‐89791‐R
- Published
- 2019
30. FBXO7 Immunoreactivity in alpha-Synuclein-Containing Inclusions in Parkinson Disease and Multiple System Atrophy
- Author
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Renate K. Hukema, Ben A. Oostra, Ping Pin Zheng, Lies Anne Severijnen, Tianna Zhao, Rob Willemsen, Marcel van der Weiden, Vincenzo Bonifati, Johan M. Kros, Pathology, and Clinical Genetics
- Subjects
Male ,Pathology ,medicine.medical_specialty ,Cytoplasmic inclusion ,Neuropathology ,Biology ,Pathology and Forensic Medicine ,Progressive supranuclear palsy ,Cellular and Molecular Neuroscience ,Atrophy ,medicine ,Humans ,Aged ,Aged, 80 and over ,Inclusion Bodies ,Synucleinopathies ,F-Box Proteins ,Putamen ,Brain ,Parkinson Disease ,General Medicine ,Human brain ,Middle Aged ,Multiple System Atrophy ,medicine.disease ,HEK293 Cells ,medicine.anatomical_structure ,Neurology ,alpha-Synuclein ,Female ,Neurology (clinical) ,Alzheimer's disease - Abstract
Mutations in the gene encoding the F-box only protein 7 (FBXO7) cause PARK15, an autosomal recessive form of juvenile parkinsonism. Although the brain pathology in PARK15 patients remains unexplored, in vivo imaging displays severe loss of nigrostriatal dopaminergic terminals. Understanding the pathogenesis of PARK15 might therefore illuminate the mechanisms of the selective dopaminergic neuronal degeneration, which could also be important for understanding idiopathic Parkinson disease (PD). The expression of FBXO7 in the human brain remains poorly characterized, and its expression in idiopathic PD and different neurodegenerative diseases has not been investigated. Here, we studied FBXO7 protein expression in brain samples of normal controls (n = 9) and from patients with PD (n = 13), multiple system atrophy (MSA) (n = 5), Alzheimer disease (AD) (n = 5), and progressive supranuclear palsy (PSP) (n = 5) using immunohistochemistry with 2 anti-FBXO7 antibodies. We detected widespread brain FBXO7 immunoreactivity, with the highest levels in neurons of the cerebral cortex, putamen, and cerebellum. There were no major differences between normal and PD brains overall, but FBXO7 immunoreactivity was detected in large proportions of α-synuclein-positive inclusions (Lewy bodies, Lewy neurites, glial cytoplasmic inclusions), where it colocalized with α-synuclein in PD and MSA cases. By contrast, weak FBXO7 immunoreactivity was occasionally detected in tau-positive inclusions in AD and PSP. These findings suggest a role for FBXO7 in the pathogenesis of the synucleinopathies. Copyright
- Published
- 2013
31. Model Systems for Understanding FXPOI
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Renate K. Hukema, Karen Usdin, and Stephanie L. Sherman
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Gynecology ,Infertility ,medicine.medical_specialty ,business.industry ,Primary ovarian insufficiency ,Ovarian Insufficiency ,Disease ,Bioinformatics ,medicine.disease ,FMR1 ,Natural history ,Epidemiology ,medicine ,Trinucleotide repeat expansion ,business - Abstract
Fragile X-associated primary ovarian insufficiency is a poorly understood cause of infertility and ovarian insufficiency. Studies to date in humans have been limited for the most part to studies of the epidemiology and natural history of the condition in women. However, related Repeat Expansion Diseases as well as cell and animal model systems are beginning to provide vital insights into the mechanisms that might be responsible for disease pathology.
- Published
- 2016
32. Mouse Models for FXTAS and the Fragile X Premutation
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Renate K. Hukema, Ronald A.M. Buijsen, Milo Careaga, Robert F. Berman, Rob Willemsen, and Molly Foote
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Genetics ,Mutation ,Ataxia ,ved/biology ,ved/biology.organism_classification_rank.species ,Biology ,medicine.disease ,medicine.disease_cause ,Phenotype ,Reverse genetics ,Fragile X syndrome ,microRNA ,medicine ,medicine.symptom ,Model organism ,Gene - Abstract
The use of model organisms is essential in order to understand the pathogenesis of many types of human disease, and this is particularly true for the study of genetic diseases such as fragile X syndrome and fragile X-associated tremor/ataxia syndrome (FXTAS). In reverse genetics, the functional study of a gene starts with the question of how a possible phenotype may derive from a specific genetic sequence (disease-causing mutation in a gene). As a first step, a gene function is purposefully altered and the effect on the normal development and/or behavior of the model organism is analyzed. In addition to providing knowledge about the cellular and molecular mechanisms underlying specific genes and their functions, animal models of human disease also provide systems for developing and validating therapeutic strategies.
- Published
- 2016
33. The clinical and pathological phenotype of C9ORF72 hexanucleotide repeat expansions
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Helenius J. Schelhaas, Yolande A.L. Pijnenburg, Harro Seelaar, Danielle Majoor-Krakauer, Dorly J. H. Deeg, Renate K. Hukema, Peter Heutink, Marion Smits, Annemieke J.M. Rozemuller, Inge de Koning, Natasja M. van Schoor, J. Roos A. de Graaf, Javier Simón-Sánchez, Leonard H. van den Berg, John C. van Swieten, Christine E. M. de Die-Smulders, Nayia Nicolaou, Joost Raaphorst, Rob Willemsen, Elise G.P. Dopper, Petra E. Cohn-Hokke, Human genetics, Neurology, Epidemiology and Data Science, Psychiatry, Pathology, EMGO - Musculoskeletal health, NCA - Neurodegeneration, EMGO+ - Musculoskeletal Health, Neuroscience Campus Amsterdam - Neurodegeneration, Urologie, Genetica & Celbiologie, Family Medicine, RS: GROW - School for Oncology and Reproduction, Clinical Genetics, and Radiology & Nuclear Medicine
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,Genotype ,DCN MP - Plasticity and memory ,tau Proteins ,Tissue Banks ,Biology ,Neuropsychological Tests ,Polymerase Chain Reaction ,Primary progressive aphasia ,Cohort Studies ,Progranulins ,SDG 3 - Good Health and Well-being ,C9orf72 ,medicine ,Humans ,Amyotrophic lateral sclerosis ,Age of Onset ,In Situ Hybridization ,Aged ,Netherlands ,Aged, 80 and over ,Neurons ,DNA Repeat Expansion ,C9orf72 Protein ,Amyotrophic Lateral Sclerosis ,Proteins ,Frontotemporal lobar degeneration ,C9orf72 repeat expansion ,Middle Aged ,medicine.disease ,Immunohistochemistry ,Pedigree ,DNA-Binding Proteins ,frontotemporal lobar degeneration ,Frontotemporal Dementia ,Intercellular Signaling Peptides and Proteins ,Female ,Neurology (clinical) ,Autopsy ,Trinucleotide repeat expansion ,Quality of hospital and integrated care [NCEBP 4] ,Frontotemporal dementia - Abstract
Item does not contain fulltext There is increasing evidence that frontotemporal dementia and amyotrophic lateral sclerosis are part of a disease continuum. Recently, a hexanucleotide repeat expansion in C9orf72 was identified as a major cause of both sporadic and familial frontotemporal dementia and amyotrophic lateral sclerosis. The aim of this study was to investigate clinical and neuropathological characteristics of hexanucleotide repeat expansions in C9orf72 in a large cohort of Dutch patients with frontotemporal dementia. Repeat expansions were successfully determined in a cohort of 353 patients with sporadic or familial frontotemporal dementia with or without amyotrophic lateral sclerosis, and 522 neurologically normal controls. Immunohistochemistry was performed in a series of 10 brains from patients carrying expanded repeats using a panel of antibodies. In addition, the presence of RNA containing GGGGCC repeats in paraffin-embedded sections of post-mortem brain tissue was investigated using fluorescence in situ hybridization with a locked nucleic acid probe targeting the GGGGCC repeat. Hexanucleotide repeat expansions in C9orf72 were found in 37 patients with familial (28.7%) and five with sporadic frontotemporal dementia (2.2%). The mean age at onset was 56.9 +/- 8.3 years (range 39-76), and disease duration 7.6 +/- 4.6 years (range 1-22). The clinical phenotype of these patients varied between the behavioural variant of frontotemporal dementia (n = 34) and primary progressive aphasia (n = 8), with concomitant amyotrophic lateral sclerosis in seven patients. Predominant temporal atrophy on neuroimaging was present in 13 of 32 patients. Pathological examination of the 10 brains from patients carrying expanded repeats revealed frontotemporal lobar degeneration with neuronal transactive response DNA binding protein-positive inclusions of variable type, size and morphology in all brains. Fluorescence in situ hybridization analysis of brain material from patients with the repeat expansion, a microtubule-associated protein tau or a progranulin mutation, and controls did not show RNA-positive inclusions specific for brains with the GGGGCC repeat expansion. The hexanucleotide repeat expansion in C9orf72 is an important cause of frontotemporal dementia with and without amyotrophic lateral sclerosis, and is sometimes associated with primary progressive aphasia. Neuropathological hallmarks include neuronal and glial inclusions, and dystrophic neurites containing transactive response DNA binding protein. Future studies are needed to explain the wide variation in clinical presentation. 01 maart 2012
- Published
- 2012
34. Widespread non-central nervous system organ pathology in fragile X premutation carriers with fragile X-associated tremor/ataxia syndrome and CGG knock-in mice
- Author
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Randi J Hagerman, Celestine S. Navarro, Claudia M. Greco, Arie P. T. Smits, Paul J. Hagerman, Renate K. Hukema, Lies Anne Severijnen, Rob Willemsen, Robert F. Berman, Elizabeth Berry-Kravis, Michael R. Hunsaker, Marian A. Spath, Flora Tassone, Johan M. Kros, Pathology, and Clinical Genetics
- Subjects
Male ,Pathology ,medicine.medical_specialty ,Ataxia ,Biology ,Article ,Pathology and Forensic Medicine ,Fragile X Mental Retardation Protein ,Mice ,Cellular and Molecular Neuroscience ,Tremor ,medicine ,Animals ,Humans ,Gene Knock-In Techniques ,Aged ,Aged, 80 and over ,Genetic Carrier Screening ,medicine.disease ,Mice, Mutant Strains ,Fragile X syndrome ,Disease Models, Animal ,Peripheral neuropathy ,medicine.anatomical_structure ,Organ Specificity ,Fragile X Syndrome ,Peripheral nervous system ,Gait Ataxia ,Female ,Intention tremor ,Enteric nervous system ,Neurology (clinical) ,medicine.symptom ,Genetics and epigenetic pathways of disease Genomic disorders and inherited multi-system disorders [NCMLS 6] ,Fragile X-associated tremor/ataxia syndrome - Abstract
Item does not contain fulltext Fragile X-associated tremor/ataxia syndrome (FXTAS) is an adult-onset neurodegenerative disorder generally presenting with intention tremor and gait ataxia, but with a growing list of co-morbid medical conditions including hypothyroidism, hypertension, peripheral neuropathy, and cognitive decline. The pathological hallmark of FXTAS is the presence of intranuclear inclusions in both neurons and astroglia. However, it is unknown to what extent such inclusions are present outside the central nervous system (CNS). To address this issue, we surveyed non-CNS organs in ten human cases with FXTAS and in a CGG repeat knock-in (CGG KI) mouse model known to possess neuronal and astroglial inclusions. We find inclusions in multiple tissues from FXTAS cases and CGG KI mice, including pancreas, thyroid, adrenal gland, gastrointestinal, pituitary gland, pineal gland, heart, and mitral valve, as well as throughout the associated autonomic ganglia. Inclusions were observed in the testes, epididymis, and kidney of FXTAS cases, but were not observed in mice. These observations demonstrate extensive involvement of the peripheral nervous system and systemic organs. The finding of intranuclear inclusions in non-CNS somatic organ systems, throughout the PNS, and in the enteric nervous system of both FXTAS cases as well as CGG KI mice suggests that these tissues may serve as potential sites to evaluate early intervention strategies or be used as diagnostic factors.
- Published
- 2011
35. BC RNA Mislocalization in the Fragile X Premutation
- Author
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Anna Iacoangeli, Henri Tiedge, Shih-Chieh Chuang, Renate K. Hukema, Rob Willemsen, Robert K. S. Wong, Ilham A. Muslimov, Taesun Eom, Dimitre G. Stefanov, and Clinical Genetics
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Male ,Untranslated region ,regulatory RNAs ,congenital, hereditary, and neonatal diseases and abnormalities ,RNA localization ,RNA transport ,Mice, Transgenic ,Regulatory Sequences, Ribonucleic Acid ,Biology ,RNA Transport ,Mice ,Seizures ,RNA, Small Cytoplasmic ,Animals ,Cognitive Dysfunction ,CGG repeats ,cognitive impairment ,Neurons ,Messenger RNA ,General Neuroscience ,Age Factors ,Glutamate receptor ,RNA ,3.1 ,General Medicine ,New Research ,CA3 Region, Hippocampal ,FMR1 ,nervous system diseases ,Mice, Inbred C57BL ,epileptiform activity ,Disease Models, Animal ,Metabotropic receptor ,Fragile X Syndrome ,Disorders of the Nervous System ,Trinucleotide Repeat Expansion ,Neuroscience - Abstract
Fragile X premutation disorder is caused by CGG triplet repeat expansions in the 5′ untranslated region of FMR1 mRNA. The question of how expanded CGG repeats cause disease is a subject of continuing debate. Our work indicates that CGG-repeat structures compete with regulatory BC1 RNA for access to RNA transport factor hnRNP A2. As a result, BC1 RNA is mislocalized in vivo, as its synapto-dendritic presence is severely diminished in brains of CGG-repeat knock-in animals (a premutation mouse model). Lack of BC1 RNA is known to cause seizure activity and cognitive dysfunction. Our working hypothesis thus predicted that absence, or significantly reduced presence, of BC1 RNA in synapto-dendritic domains of premutation animal neurons would engender cognate phenotypic alterations. Testing this prediction, we established epileptogenic susceptibility and cognitive impairments as major phenotypic abnormalities of CGG premutation mice. In CA3 hippocampal neurons of such animals, synaptic release of glutamate elicits neuronal hyperexcitability in the form of group I metabotropic glutamate receptor–dependent prolonged epileptiform discharges. CGG-repeat knock-in animals are susceptible to sound-induced seizures and are cognitively impaired as revealed in the Attentional Set Shift Task. These phenotypic disturbances occur in young-adult premutation animals, indicating that a neurodevelopmental deficit is an early-initial manifestation of the disorder. The data are consistent with the notion that RNA mislocalization can contribute to pathogenesis.
- Published
- 2018
36. An Integrative Study of Protein-RNA Condensates Identifies Scaffolding RNAs and Reveals Players in Fragile X-Associated Tremor/Ataxia Syndrome
- Author
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Nieves Lorenzo-Gotor, Ellen Gelpi, Gian Gaetano Tartaglia, Mariona Gelabert-Baldrich, Fernando Cid-Samper, Lies-Anne Severijnen, Benjamin Lang, Benedetta Bolognesi, Renate K. Hukema, Riccardo Delli Ponti, Teresa Botta-Orfila, and Clinical Genetics
- Subjects
Genetics and Molecular Biology (all) ,0301 basic medicine ,Untranslated region ,RNA, Untranslated ,RNA-binding protein ,Biochemistry ,Fragile X Mental Retardation Protein ,Mice ,RBP ,Chlorocebus aethiops ,Tremor ,Protein Interaction Maps ,lcsh:QH301-705.5 ,Ribonucleoprotein ,Inclusion Bodies ,Serine-Arginine Splicing Factors ,Brain ,RNA-Binding Proteins ,Ribonucleoproteins ,RNA splicing ,COS Cells ,Fragile X-associated tremor/ataxia syndrome ,Scaffolding RNA ,CGG repeat expansion ,RNA binding proteins ,congenital, hereditary, and neonatal diseases and abnormalities ,In silico ,RNA Splicing ,Phase separation ,Computational biology ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Article ,03 medical and health sciences ,medicine ,Animals ,Humans ,Computer Simulation ,Neurodegeneration ,Cell Nucleus ,FMR1 premutation ,fragile X-associated tremor/ataxia syndrome ,FXTAS ,neurodegeneration ,phase separation ,RNA aggregates ,scaffolding RNA ,TRA2A splicing regulator ,Biochemistry, Genetics and Molecular Biology (all) ,RNA ,Reproducibility of Results ,medicine.disease ,FMR1 ,nervous system diseases ,030104 developmental biology ,lcsh:Biology (General) ,Fragile X Syndrome ,Ataxia - Abstract
Summary Recent evidence indicates that specific RNAs promote the formation of ribonucleoprotein condensates by acting as scaffolds for RNA-binding proteins (RBPs). We systematically investigated RNA-RBP interaction networks to understand ribonucleoprotein assembly. We found that highly contacted RNAs are structured, have long UTRs, and contain nucleotide repeat expansions. Among the RNAs with such properties, we identified the FMR1 3′ UTR that harbors CGG expansions implicated in fragile X-associated tremor/ataxia syndrome (FXTAS). We studied FMR1 binding partners in silico and in vitro and prioritized the splicing regulator TRA2A for further characterization. In a FXTAS cellular model, we validated the TRA2A-FMR1 interaction and investigated implications of its sequestration at both transcriptomic and post-transcriptomic levels. We found that TRA2A co-aggregates with FMR1 in a FXTAS mouse model and in post-mortem human samples. Our integrative study identifies key components of ribonucleoprotein aggregates, providing links to neurodegenerative disease and allowing the discovery of therapeutic targets., Graphical Abstract, Highlights • Highly contacted granule RNAs are structured and contain long, repetitive UTRs • Mutations related with FXTAS increase FMR1 scaffolding propensity • TRA2A co-aggregates with FMR1 in FXTAS mouse model and in post-mortem human samples • TRA2 sequestration has both transcriptomic and post-transcriptomic implications, Cid-Samper et al. analyze protein-RNA networks and identify properties of RNA scaffolds within biological condensates. They find that CGG repeats in the 3′ UTR of FMR1 attract several proteins, including the splicing factor TRA2A that co-aggregates in fragile X-associated tremor/ataxia syndrome (FXTAS).
- Published
- 2018
37. Reversibility of neuropathology and motor deficits in an inducible mouse model for FXTAS
- Author
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Robert F. Berman, Nicolas Charlet-Berguerand, Rob F M Verhagen, Chris Raske, Lies Anne Severijnen, Lisanne van Dessel, Alex Maas, Rob Willemsen, Ronald A.M. Buijsen, Paul J. Hagerman, Renate K. Hukema, Ingeborg Nieuwenhuizen-Bakker, Martijn Schonewille, Chris I. De Zeeuw, Clinical Genetics, Neurosciences, Clinical Chemistry, Internal Medicine, Molecular Genetics, Netherlands Institute for Neuroscience (NIN), Erasmus University Medical Center [Rotterdam] (Erasmus MC), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Royal Netherlands Academy of Arts and Sciences (KNAW), University of California [Davis] (UC Davis), and University of California
- Subjects
Untranslated region ,Eye Movements ,[SDV]Life Sciences [q-bio] ,Intranuclear Inclusion Bodies ,Gene Expression ,Neurodegenerative ,Medical and Health Sciences ,Transgenic ,Mice ,Genes, Reporter ,Tremor ,2.1 Biological and endogenous factors ,Aetiology ,ComputingMilieux_MISCELLANEOUS ,Genetics (clinical) ,Genetics & Heredity ,Genetics ,Parkinsonism ,Brain ,General Medicine ,Articles ,Biological Sciences ,Phenotype ,3. Good health ,Protein Transport ,Neurological ,Intention tremor ,medicine.symptom ,Protein Binding ,Genetically modified mouse ,Ataxia ,Intellectual and Developmental Disabilities (IDD) ,Mice, Transgenic ,Neuropathology ,Biology ,Rare Diseases ,medicine ,Animals ,Humans ,Reporter ,Molecular Biology ,Animal ,Ubiquitin ,Neurosciences ,RNA ,medicine.disease ,Brain Disorders ,Disease Models, Animal ,Genes ,Fragile X Syndrome ,Disease Models ,Cancer research ,Peptides ,Trinucleotide Repeat Expansion - Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder affecting carriers of the fragile X-premutation, who have an expanded CGG repeat in the 5'-UTR of the FMR1 gene. FXTAS is characterized by progressive development of intention tremor, ataxia, parkinsonism and neuropsychological problems. The disease is thought to be caused by a toxic RNA gain-of-function mechanism, and the major hallmark of the disease is ubiquitin-positive intranuclear inclusions in neurons and astrocytes. We have developed a new transgenic mouse model in which we can induce expression of an expanded repeat in the brain upon doxycycline (dox) exposure (i.e. Tet-On mice). This Tet-On model makes use of the PrP-rtTA driver and allows us to study disease progression and possibilities of reversibility. In these mice, 8 weeks of dox exposure was sufficient to induce the formation of ubiquitin-positive intranuclear inclusions, which also stain positive for the RAN translation product FMRpolyG. Formation of these inclusions is reversible after stopping expression of the expanded CGG RNA at an early developmental stage. Furthermore, we observed a deficit in the compensatory eye movements of mice with inclusions, a functional phenotype that could be reduced by stopping expression of the expanded CGG RNA early in the disease development. Taken together, this study shows, for the first time, the potential of disease reversibility and suggests that early intervention might be beneficial for FXTAS patients.
- Published
- 2015
38. Antagonistic sensory cues generate gustatory plasticity in Caenorhabditis elegans
- Author
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Suzanne Rademakers, Renate K. Hukema, Jan Burghoorn, Martijn P. J. Dekkers, Gert Jansen, and Cell biology
- Subjects
Sensory system ,Sodium Chloride ,Models, Biological ,General Biochemistry, Genetics and Molecular Biology ,Article ,Species Specificity ,GTP-Binding Proteins ,Neuroplasticity ,Animals ,Neurons, Afferent ,Receptor ,Caenorhabditis elegans ,Molecular Biology ,Cyclic GMP ,Neuronal Plasticity ,General Immunology and Microbiology ,biology ,Kinase ,General Neuroscience ,Beta adrenergic receptor kinase ,Chemotaxis ,Anatomy ,biology.organism_classification ,Cell biology ,beta-Adrenergic Receptor Kinases ,Taste ,biology.protein ,Calcium ,Signal transduction ,Cues ,Signal Transduction - Abstract
Caenorhabditis elegans shows chemoattraction to 0.1-200 mM NaCl, avoidance of higher NaCl concentrations, and avoidance of otherwise attractive NaCl concentrations after prolonged exposure to NaCl (gustatory plasticity). Previous studies have shown that the ASE and ASH sensory neurons primarily mediate attraction and avoidance of NaCl, respectively. Here we show that balances between at least four sensory cell types, ASE, ASI, ASH, ADF and perhaps ADL, modulate the response to NaCl. Our results suggest that two NaCl-attraction signalling pathways exist, one of which uses Ca(2+)/cGMP signalling. In addition, we provide evidence that attraction to NaCl is antagonised by G-protein signalling in the ASH neurons, which is desensitised by the G-protein-coupled receptor kinase GRK-2. Finally, the response to NaCl is modulated by G-protein signalling in the ASI and ADF neurons, a second G-protein pathway in ASH and cGMP signalling in neurons exposed to the body fluid.
- Published
- 2006
39. Cerebral Protein Synthesis in a Knockin Mouse Model of the Fragile X Premutation
- Author
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Michael Kader, Mei Qin, Renate K. Hukema, Tianjian Huang, Carolyn Beebe Smith, Zhong-Hua Liu, Zachary Zeidler, Thomas V Burlin, and Zengyan Xia
- Subjects
Male ,Untranslated region ,medicine.medical_specialty ,congenital, hereditary, and neonatal diseases and abnormalities ,protein synthesis ,Mice, Transgenic ,Biology ,lcsh:RC321-571 ,Fragile X Mental Retardation Protein ,Mice ,Internal medicine ,medicine ,Protein biosynthesis ,Animals ,Humans ,Gene silencing ,RNA, Messenger ,Fmr1 ,Gene ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Cerebral Cortex ,Genetics ,Analysis of Variance ,Messenger RNA ,General Neuroscience ,fragile X premutation ,medicine.disease ,FMR1 ,nervous system diseases ,Mice, Inbred C57BL ,Fragile X syndrome ,Disease Models, Animal ,Endocrinology ,Fragile X Syndrome ,Mutation ,Knockout mouse ,Autoradiography ,Original Article ,FXTAS ,Neurology (clinical) ,FMRP ,Trinucleotide Repeat Expansion - Abstract
The (CGG)n-repeat in the 5′-untranslated region of the fragile X mental retardation gene ( FMR1) gene is polymorphic and may become unstable on transmission to the next generation. In fragile X syndrome, CGG repeat lengths exceed 200, resulting in silencing of FMR1 and absence of its protein product, fragile X mental retardation protein (FMRP). CGG repeat lengths between 55 and 200 occur in fragile X premutation (FXPM) carriers and have a high risk of expansion to a full mutation on maternal transmission. FXPM carriers have an increased risk for developing progressive neurodegenerative syndromes and neuropsychological symptoms. FMR1 mRNA levels are elevated in FXPM, and it is thought that clinical symptoms might be caused by a toxic gain of function due to elevated FMR1 mRNA. Paradoxically, FMRP levels decrease moderately with increasing CGG repeat length in FXPM. Lowered FMRP levels may also contribute to the appearance of clinical problems. We previously reported increases in regional rates of cerebral protein synthesis (rCPS) in the absence of FMRP in an Fmr1 knockout mouse model and in a FXPM knockin (KI) mouse model with 120 to 140 CGG repeats in which FMRP levels are profoundly reduced (80%–90%). To explore whether the concentration of FMRP contributes to the rCPS changes, we measured rCPS in another FXPM KI model with a similar CGG repeat length and a 50% reduction in FMRP. In all 24 brain regions examined, rCPS were unaffected. These results suggest that even with 50% reductions in FMRP, normal protein synthesis rates are maintained.
- Published
- 2014
40. A new inducible transgenic mouse model for C9orf72-associated GGGGCC repeat expansion supports a gain-of-function mechanism in C9orf72-associated ALS and FTD
- Author
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Lies-Anne Severijnen, Fréderike W. Riemslagh, Rob Willemsen, Nicolas Charlet-Berguerand, Renate K. Hukema, Alex Maas, John C. van Swieten, Dieter Edbauer, Shamiram Melhem, Herma C. van der Linde, Human genetics, Neurology, NCA - neurodegeneration, Erasmus University Medical Center [Rotterdam] (Erasmus MC), German Research Center for Neurodegenerative Diseases - Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Clinical Genetics, Molecular Genetics, CHARLET BERGUERAND, NICOLAS, and Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Pathology ,metabolism [Inclusion Bodies] ,Heterogeneous nuclear ribonucleoprotein ,Cytoplasmic inclusion ,[SDV]Life Sciences [q-bio] ,C9orf72 ,metabolism [Ubiquitin] ,Letter to the Editor ,genetics [Frontotemporal Dementia] ,ComputingMilieux_MISCELLANEOUS ,Inclusion Bodies ,DNA Repeat Expansion ,Brain ,FTD ,metabolism [Proteins] ,3. Good health ,[SDV] Life Sciences [q-bio] ,genetics [Amyotrophic Lateral Sclerosis] ,Frontotemporal Dementia ,metabolism [Frontotemporal Dementia] ,Genetically modified mouse ,medicine.medical_specialty ,Transgene ,Inducible mouse model ,Mice, Transgenic ,Biology ,Pathology and Forensic Medicine ,Cellular and Molecular Neuroscience ,medicine ,Animals ,Humans ,ddc:610 ,GGGGCC repeat ,C9orf72 Protein ,Ubiquitin ,metabolism [Amyotrophic Lateral Sclerosis] ,Amyotrophic Lateral Sclerosis ,Proteins ,Molecular biology ,genetics [Proteins] ,Disease Models, Animal ,Retraction Note ,metabolism [Brain] ,Neurology (clinical) ,ALS ,C9orf72 protein, human ,RNA gain-of-function ,Trinucleotide repeat expansion - Abstract
Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are two neurodegenerative disorders that share clinical, genetic and pathological overlap. In 2011, a hexanucleotide repeat (GGGGCC) expansion in the ‘chromosome 9 open reading frame 72’ (C9orf72) gene was identified as a cause of FTD and ALS [1,2]. This mutation has proven to be the most common genetic defect in the neurodegenerative field, especially in FTD and ALS [3]. Patients harboring the C9orf72 repeat expansion can develop FTD, ALS or both and are therefore associated with wide clinical diversity [4]. There have been multiple hypotheses about the underlying mechanisms by which the repeat expansion leads to neuropathology, including loss-of-function caused by haploinsufficiency of the endogenous C9orf72 protein product or gain-of-function induced by either RNA or protein toxicity. Either free RNA molecules containing the repeat expansion or RNA foci that sequester proteins could be toxic for cells. Alternatively, a pathogenic mechanism has been proposed for the production of toxic dipeptide repeat proteins (DPR) by repeat-associated non-AUG translation (RAN) of the repeat [5,6]. Interestingly, to differentiate between repeat “RNA-only” and DPR protein toxicity fruit fly models carrying a range of pure and RNA-only repeats have been generated. These studies demonstrated that the major toxic species were the DPR proteins [7]. Here we report on an “RNA-only” gain-of-function mouse model. To study the intrinsic effect of the repeat without assessing its effect on the C9orf72 gene, we created a spatially and temporally inducible transgenic mouse model. This mouse model has a repeat size of 80 GGGGCC-repeats, without human flanking regions, which may affect repeat translation. This repeat was cloned in the 5′ UTR of a GFP reporter gene and controlled by a tetracycline responsive element (TRE) promoter (Figure 1A). To enable expression of the TRE-construct we created bigenic mice that possess both the TRE-construct and the tetracycline-responsive transcriptional activator (rtTA) under a general heterogeneous nuclear ribonucleoprotein (hnRNP) promoter [8]. Expression of the repeat was turned on after weaning by adding doxycycline (dox) to the drinking water. Expression of the repeat construct can be stopped at any time by withdrawal of dox, allowing for reversibility studies (Figure 1A; more information about the creation of the model can be found in Additional file 1). After generation of transgenic mice, the repeat size remained stable for multiple generations (data not shown). GFP expression was seen in bigenic mice as soon as 4 days after dox treatment started and remained stable over time (assessed by western blot of liver homogenates, data not shown). Next to liver, multiple other tissues showed GFP expression including lung, kidney and brain; with most prominent expression in the striatum (Figure 1B) and the cuneate nucleus in the brainstem. Figure 1 Expression of 80GGGGCC-repeats leads to the formation of ubiquitin-positive inclusions in mouse brain. A) Schematic of the model used to create the inducible mice. Simultaneous expression of rtTA and doxycycline treatment are needed to drive expression ... Both ubiquitin-positive, TDP-43-positive and TDP-43 negative neuronal and cytoplasmic inclusions are pathological hallmarks in post mortem brain tissue from C9orf72 FTD and ALS patients. We used the presence of inclusions as a readout for the effect of expression of the repeat in our “RNA-only” gain-of-function ALS/FTD model [9,10]. We found ubiquitin-positive inclusions in those brain regions that express high levels of GFP, including the striatum (Figure 1C) and the cuneate nucleus of bigenic mice after twelve weeks of dox treatment (n = 7 mice per group). Inclusions were found in the nuclei and the neuropil in striatum and mainly in the nuclei in the cuneate nucleus. The presence of ubiquitin-positive inclusions in our mouse model is a shared phenomenon with non-C9orf72 mouse models of ALS and FTD [11,12]. We did not observe any TDP-43 positive nor p409/410 TDP-43 positive inclusions in our mouse model after twelve weeks of dox treatment, despite the positive staining in a C9orf72 patient hippocampus control (data not shown). TDP-43 inclusions might only appear after prolonged expression of the repeat or additional genetic or environmental factors might be needed to drive TDP-43 dysfunction. Importantly, TDP-43 function could also be affected without the presence of TDP-43 positive aggregates [13]. The absence of DPR pathology was assessed with a poly-GA antibody [6]. We could not detect poly-GA aggregation in brain tissue from bigenic mice, but only revealed GA-positive inclusions in C9orf72 patient hippocampus control material illustrating lack of DPR pathology in this mouse model (Figure 2). The mice did not develop any obvious behavioral phenotype and showed no cell loss. The neurotoxic effect of the C9orf72 hexarepeat expansion has been suggested by both RNA- and protein-mediated pathology [7]. Due to lack of DPR pathology, this mouse is a good model to investigate whether toxicity can be driven by the repeat RNA only. Future studies focusing on molecular changes and behavior deficits in our mouse model can provide additional insight in disease progression, reversibility and create options for therapeutic intervention. In conclusion, we demonstrate that solely expression of the GGGGCC repeat outside the C9orf72 context results in ubiquitin-positive inclusions, which is a pathological hallmark in postmortem brain from ALS and FTD patients. Our data on this first C9orf72 mouse model argues in favor for a gain-of-function pathological mechanism in C9orf72 associated ALS and FTD. Figure 2 Absence of DPR pathology in brain of 80GGGGCC RNA expressing mouse. A) GA positive inclusions in the hippocampus of C9orf72FTD patient. B) the striatum of bigenic mice treated with dox for 12 weeks shows no GA positive inclusions. All animal experiments were conducted with the permission of the local animal welfare committee (DEC). Experiments on human brain material were done under informed consent and approved by the Medical Ethical Test Committee (METC). Human paraffin embedded brain material was provided by the Dutch brain bank (Nederlandse Hersenbank NHB).
- Published
- 2014
41. Mouse models of the fragile X premutation and fragile X-associated tremor/ataxia syndrome
- Author
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Isaac N. Pessah, Karen Usdin, David L. Nelson, Renate K. Hukema, Elizabeth Pintado, Dalyir I. Pretto, Nicholas Charlet-Bergeurand, Rob Willemsen, Robert F. Berman, R. Frank Kooy, Ronald A.M. Buijsen, Zachary A. Zalewski, and Clinical Genetics
- Subjects
medicine.medical_specialty ,Ataxia ,Neurology ,Dendritic spine ,Cognitive Neuroscience ,Intellectual and Developmental Disabilities (IDD) ,Population ,Review ,Neurodegenerative ,Mouse models ,Pathology and Forensic Medicine ,Rare Diseases ,Clinical Research ,Behavioral and Social Science ,medicine ,Genetics ,2.1 Biological and endogenous factors ,Psychology ,CGG trinucleotide repeat ,Intranuclear inclusions ,Aetiology ,education ,FMR1 ,Pediatric ,education.field_of_study ,Neurosciences ,RNA toxicity ,medicine.disease ,Fragile X premutation ,Brain Disorders ,Orphan Drug ,Mental Health ,Fragile X Syndrome ,Pediatrics, Perinatology and Child Health ,Neurological ,Human medicine ,Neurology (clinical) ,FXTAS ,medicine.symptom ,Trinucleotide repeat expansion ,FMRP ,Neurocognitive ,Neuroscience ,Fragile X-associated tremor/ataxia syndrome - Abstract
Carriers of the fragile X premutation (FPM) have CGG trinucleotide repeat expansions of between 55 and 200 in the 5'-UTR of FMR1, compared to a CGG repeat length of between 5 and 54 for the general population. Carriers were once thought to be without symptoms, but it is now recognized that they can develop a variety of early neurological symptoms as well as being at risk for developing the late onset neurodegenerative disorder fragile X-associated tremor/ataxia syndrome (FXTAS). Several mouse models have contributed to our understanding of FPM and FXTAS, and findings from studies using these models are summarized here. This review also discusses how this information is improving our understanding of the molecular and cellular abnormalities that contribute to neurobehavioral features seen in some FPM carriers and in patients with FXTAS. Mouse models show much of the pathology seen in FPM carriers and in individuals with FXTAS, including the presence of elevated levels of Fmr1 mRNA, decreased levels of fragile X mental retardation protein, and ubiquitin-positive intranuclear inclusions. Abnormalities in dendritic spine morphology in several brain regions are associated with neurocognitive deficits in spatial and temporal memory processes, impaired motor performance, and altered anxiety. In vitro studies have identified altered dendritic and synaptic architecture associated with abnormal Ca2+ dynamics and electrical network activity. FPM mice have been particularly useful in understanding the roles of Fmr1 mRNA, fragile X mental retardation protein, and translation of a potentially toxic polyglycine peptide in pathology. Finally, the potential for using these and emerging mouse models for preclinical development of therapies to improve neurological function in FXTAS is considered.
- Published
- 2014
42. 'Induced expression of expanded CGG RNA causes mitochondrial dysfunction in vivo.'
- Author
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Rini de Crom, Chris Raske, Alex Maas, Robert F. Berman, Ingeborg Nieuwenhuizen-Bakker, Renate K. Hukema, Lies Anne Severijnen, Michelle Minneboo, Rob Willemsen, Johan M. Kros, Paul J. Hagerman, Ronald A.M. Buijsen, Clinical Genetics, Molecular Genetics, Cell biology, and Pathology
- Subjects
Apoptosis ,enhanced green fluorescent protein ,Mitochondrion ,Neurodegenerative ,Transgenic ,Repetitive Sequences ,Pathogenesis ,Mice ,eGFP ,caspase 3 ,Tremor ,2.1 Biological and endogenous factors ,Aetiology ,Tet-On ,gpx ,Anti-Bacterial Agents ,Mitochondria ,Liver ,Doxycycline ,Neurological ,Fragile X-associated tremor/ataxia syndrome ,ataxia syndrome ,medicine.symptom ,rtTA ,Genetically modified mouse ,dox ,congenital, hereditary, and neonatal diseases and abnormalities ,Ataxia ,Transgene ,Intellectual and Developmental Disabilities (IDD) ,inducible mouse model ,Biology ,Promoter Regions ,cytochrome C ,Rare Diseases ,Genetic ,In vivo ,Report ,medicine ,Genetics ,Animals ,Molecular Biology ,Repetitive Sequences, Nucleic Acid ,Nucleic Acid ,Animal ,gpx-1 ,Neurosciences ,RNA ,Cell Biology ,Molecular biology ,reverse tetracycline transactivator ,Brain Disorders ,Fatty Liver ,Orphan Drug ,Fragile X-associated tremor ,CGG repeat ,Tet Responsive Element ,gluthation peroxidase ,Fragile X Syndrome ,Disease Models ,FXTAS ,TRE ,Biochemistry and Cell Biology ,Reactive Oxygen Species ,RNA gain-of-function ,Developmental Biology - Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder affecting carriers of premutation forms of the FMR1 gene, resulting in a progressive development of tremor, ataxia and neuropsychological problems. The disease is caused by an expanded CGG repeat in the FMR1 gene, leading to an RNA gain-of-function toxicity mechanism. In order to study the pathogenesis of FXTAS, new inducible transgenic mouse models have been developed that expresses either 11CGGs or 90CGGs at the RNA level under control of a Tet-On promoter. When bred to an hnRNP-rtTA driver line, doxycycline (dox) induced expression of the transgene could be found in almost all tissues. Dox exposure resulted in loss of weight and death within 5 d for the 90CGG RNA expressing mice. Immunohistochemical examination of tissues of these mice revealed steatosis and apoptosis in the liver. Decreased expression of GPX1 and increased expression of cytochrome C is found. These effects were not seen in mice expressing a normal sized 11CGG repeat. In conclusion, we were able to show in vivo that expression of an expanded CGG-repeat rather than overexpression of a normal CGG-repeat causes pathology. In addition, we have shown that expanded CGG RNA expression can cause mitochondrial dysfunction by regulating expression levels of several markers. Although FTXAS patients do not display liver abnormalities, our findings contribute to understanding of the molecular mechanisms underlying toxicity of CGG repeat RNA expression in an animal model. In addition, the dox inducible mouse lines offer new opportunities to study therapeutic interventions for FXTAS.
- Published
- 2014
43. The CGG repeat and the FMR1 gene
- Author
-
Renate K, Hukema and Ben A, Oostra
- Subjects
Male ,Sequence Analysis, DNA ,DNA Methylation ,Polymerase Chain Reaction ,Blotting, Southern ,Fragile X Mental Retardation Protein ,Mice ,Gene Expression Regulation ,Trinucleotide Repeats ,Animals ,Humans ,Sulfites ,Female ,RNA, Messenger ,Plasmids - Abstract
This chapter intends to provide the different DNA and protein methods for analysis of the repeat in the FMR1 gene, both in humans and in mouse models. The methods to determine the CGG repeat size include Southern blot analysis, polymerase chain reaction (PCR), and methylation status analysis, including bisulfite treatment. The methods to determine expression include analysis of RNA levels and protein levels.
- Published
- 2013
44. The CGG Repeat and the FMR1 Gene
- Author
-
Renate K. Hukema and Ben A. Oostra
- Subjects
Genetics ,Bisulfite ,Regulation of gene expression ,Sequence analysis ,law ,Bisulfite sequencing ,DNA methylation ,Biology ,Trinucleotide repeat expansion ,Molecular biology ,Polymerase chain reaction ,Southern blot ,law.invention - Abstract
This chapter intends to provide the different DNA and protein methods for analysis of the repeat in the FMR1 gene, both in humans and in mouse models. The methods to determine the CGG repeat size include Southern blot analysis, polymerase chain reaction (PCR), and methylation status analysis, including bisulfite treatment. The methods to determine expression include analysis of RNA levels and protein levels.
- Published
- 2013
45. Mouse Models of the Fragile X Premutation and the Fragile X Associated Tremor/Ataxia Syndrome
- Author
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Michael R. Hunsaker, Gloria Arque, Renate K. Hukema, Rob Willemsen, and Robert F. Berman
- Subjects
Fragile x ,Ataxia ,Mice, Transgenic ,Disease ,Biology ,medicine.disease_cause ,Article ,Pathogenesis ,Fragile X Mental Retardation Protein ,Mice ,Animal model ,Tremor ,medicine ,Animals ,Humans ,Genetics ,Mutation ,Behavior, Animal ,medicine.disease ,Fragile X syndrome ,Disease Models, Animal ,Fragile X Syndrome ,medicine.symptom ,Fragile X-associated tremor/ataxia syndrome - Abstract
The use of mutant mouse models of neurodevelopmental and neurodegenerative disease is essential in order to understand the pathogenesis of many genetic diseases such as fragile X syndrome and fragile X-associated tremor/ataxia syndrome (FXTAS). The choice of which animal model is most suitable to mimic a particular disease depends on a range of factors, including anatomical, physiological, and pathological similarities; presence of orthologs of genes of interest; and conservation of basic cell biological and metabolic processes. In this chapter, we will discuss two mouse models of the fragile X premutation which have been generated to study the pathogenesis of FXTAS and the effects of potential therapeutic interventions. Behavioral, molecular, neuropathological, and endocrine features of the mouse models and their relation to human FXTAS are discussed.
- Published
- 2011
46. Sam68 sequestration and partial loss of function are associated with splicing alterations in FXTAS patients
- Author
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Chantal Sellier, Anne Schneider, Frédérique Rau, Yilei Liu, Stéphane Richard, Nicolas Charlet-Berguerand, Renate K. Hukema, David J. Elliott, Rob Willemsen, Renata Gattoni, Flora Tassone, Paul J. Hagerman, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Newcastle University [Newcastle], University of California [Davis] (UC Davis), University of California, Erasmus University Medical Center [Rotterdam] (Erasmus MC), McGill University = Université McGill [Montréal, Canada], CHARLET BERGUERAND, NICOLAS, Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), University of California (UC), and Clinical Genetics
- Subjects
[SDV]Life Sciences [q-bio] ,RNA-binding protein ,Heterogeneous ribonucleoprotein particle ,Heterogeneous-Nuclear Ribonucleoproteins ,Mice ,chemistry.chemical_compound ,0302 clinical medicine ,Chlorocebus aethiops ,MBNL1 ,Enzyme Inhibitors ,Phosphorylation ,ComputingMilieux_MISCELLANEOUS ,Genetics ,0303 health sciences ,Fragile X Tremor/Ataxia Syndrome ,General Neuroscience ,RNA-Binding Proteins ,Cell biology ,DNA-Binding Proteins ,[SDV] Life Sciences [q-bio] ,COS Cells ,RNA splicing ,medicine.symptom ,congenital, hereditary, and neonatal diseases and abnormalities ,Ataxia ,Biology ,Article ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,medicine ,Animals ,Humans ,Spiro Compounds ,RNA, Messenger ,Molecular Biology ,Adaptor Proteins, Signal Transducing ,Pyrans ,Repetitive Sequences, Nucleic Acid ,030304 developmental biology ,Cell Nucleus ,General Immunology and Microbiology ,Alternative splicing ,medicine.disease ,nervous system diseases ,Alternative Splicing ,chemistry ,Fragile X Syndrome ,Tyrosine ,030217 neurology & neurosurgery ,Fragile X-associated tremor/ataxia syndrome - Abstract
Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) is a neurodegenerative disorder caused by expansion of 55-200 CGG repeats in the 5'-UTR of the FMR1 gene. FXTAS is characterized by action tremor, gait ataxia and impaired executive cognitive functioning. It has been proposed that FXTAS is caused by titration of RNA-binding proteins by the expanded CGG repeats. Sam68 is an RNA-binding protein involved in alternative splicing regulation and its ablation in mouse leads to motor coordination defects. Here, we report that mRNAs containing expanded CGG repeats form large and dynamic intranuclear RNA aggregates that recruit several RNA-binding proteins sequentially, first Sam68, then hnRNP-G and MBNL1. Importantly, Sam68 is sequestered by expanded CGG repeats and thereby loses its splicing-regulatory function. Consequently, Sam68-responsive splicing is altered in FXTAS patients. Finally, we found that regulation of Sam68 tyrosine phosphorylation modulates its localization within CGG aggregates and that tautomycin prevents both Sam68 and CGG RNA aggregate formation. Overall, these data support an RNA gain-of-function mechanism for FXTAS neuropathology, and suggest possible target routes for treatment options. The EMBO Journal (2010) 29, 1248-1261. doi:10.1038/emboj.2010.21; Published online 25 February 2010
- Published
- 2010
47. Signaling proteins that regulate NaCL chemotaxis responses modulate longevity in C. elegans
- Author
-
Renate K. Hukema, Michel R. Leroux, Nathan J. Bialas, Martijn P. J. Dekkers, Gert Jansen, Hannes Lans, Molecular Genetics, Cell biology, and Clinical Genetics
- Subjects
G protein ,General Neuroscience ,Protein subunit ,Chemotaxis ,Longevity ,Amphid ,Sensory system ,Biology ,Sodium Chloride ,Heterotrimeric GTP-Binding Proteins ,General Biochemistry, Genetics and Molecular Biology ,Cell biology ,History and Philosophy of Science ,Taste ,Animals ,Signal transduction ,Caenorhabditis elegans ,Sensory cue ,Function (biology) ,Signal Transduction - Abstract
The lifespan of the nematode Caenorhabditis elegans is regulated by sensory signals detected by the amphid neurons. In these neurons, C. elegans expresses at least 14 Gα subunits and a Gγ subunit. We have identified seven sensory Gα subunits that modulate lifespan. Genetic experiments suggest that multiple sensory signaling pathways exist that modulate lifespan and that some G proteins function in multiple pathways, most of which, but probably not all, involve insulinIGF-1 like signaling. Interestingly, of the sensory G proteins involved in regulating lifespan, only one Gα probably functions directly in the detection of sensory cues. The other G proteins seem to function in modulating the sensitivity of the sensory neurons. We hypothesize that in addition to the mere detection of sensory cues, regulation of the sensitivity of sensory neurons also plays a role in the regulation of lifespan.
- Published
- 2009
48. CGG-repeat length and neuropathological and molecular correlates in a mouse model for fragile X-associated tremor/ataxia syndrome
- Author
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Ben A. Oostra, Judith R. Brouwer, Renate K. Hukema, Karin Huizer, Lies Anne Severijnen, Rob Willemsen, Robert F. Berman, and Clinical Genetics
- Subjects
Untranslated region ,Male ,congenital, hereditary, and neonatal diseases and abnormalities ,Ataxia ,Intranuclear Inclusion Bodies ,Biology ,Biochemistry ,Article ,Gene product ,Cellular and Molecular Neuroscience ,Fragile X Mental Retardation Protein ,Mice ,medicine ,Gene silencing ,Animals ,RNA, Messenger ,Genetics ,Cerebral Cortex ,Age Factors ,medicine.disease ,FMR1 ,nervous system diseases ,Fragile X syndrome ,Disease Models, Animal ,Fragile X Syndrome ,medicine.symptom ,Trinucleotide repeat expansion ,Trinucleotide Repeat Expansion ,Fragile X-associated tremor/ataxia syndrome - Abstract
The 5′untranslated region (UTR) of the FMR1 gene contains a CGG-repeat, which may become unstable upon transmission to the next generation. When repeat length exceeds 200, the FMR1 gene generally undergoes methylation-mediated transcriptional silencing. The subsequent absence of the gene product Fragile X Mental Retardation Protein (FMRP) causes the mental retardation seen in fragile X patients. A CGG-repeat length between 55 and 200 trinucleotides has been termed the premutation (PM). Predominantly elderly male PM carriers are at risk of developing a progressive neurodegenerative disorder: fragile X-associated tremor/ataxia syndrome (FXTAS). All PM carriers have elevated FMR1 mRNA levels, in spite of slightly decreased FMRP levels. The presence of intranuclear ubiquitin-positive inclusions in many brain regions is a neuropathological hallmark of FXTAS. Studies in humans attempting to correlate neuropathological outcomes with molecular measures are difficult because of the limited availability of tissue. Therefore, we have used the expanded CGG-repeat knock-in mouse model of FXTAS to examine the relationship between the molecular and neuropathological parameters in brain. We present Fmr1 mRNA and Fmrp levels and the presence of intranuclear inclusions at different repeat lengths. Contrary to existing hypotheses, our results suggest that inclusion formation may not depend on the elevation per se of Fmr1 transcript levels in aged CGG mice.
- Published
- 2008
49. Corrigendum
- Author
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Wouter Kamphorst, John C. van Swieten, Petra Frick, Vincenzo Bonifati, Manuela Neumann, Renate K. Hukema, Annemieke J.M. Rozemuller, David Hondius, E. Bert Bakker, Wang Zheng Chiu, Joyce H.G. Lebbink, Sjoerd G. van Duinen, August B. Smit, Guido J. Breedveld, Ka Wan Li, Gert Jan Lammers, H. Seelaar, Annemieke J.M.H. Verkerk, Lies Anne Severijnen, Tsz Hang Wong, and Rob Willemsen
- Subjects
Genetics ,business.industry ,Mutation (genetic algorithm) ,Medicine ,Neurology (clinical) ,business - Published
- 2015
50. Use of model systems to understand the etiology of fragile X-associated primary ovarian insufficiency (FXPOI)
- Author
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Karen Usdin, Charles A. Easley, Renate K. Hukema, Eliza Curnow, Rob Willemsen, Stephanie L. Sherman, Maria-Isabel Tejada, Peng Jin, and Clinical Genetics
- Subjects
medicine.medical_specialty ,Cognitive Neuroscience ,Granulosa cell ,Review ,Primary ovarian insufficiency ,Biology ,Bioinformatics ,Pathology and Forensic Medicine ,Hypergonadotropic hypogonadism ,SDG 3 - Good Health and Well-being ,Internal medicine ,medicine ,Repeat expansion disorder ,Premature ovarian failure ,medicine.disease ,FMR1 ,Human genetics ,3. Good health ,Fragile X syndrome ,Endocrinology ,Fertility ,CGG repeat ,Pediatrics, Perinatology and Child Health ,Neurology (clinical) ,Animal studies ,Folliculogenesis - Abstract
Fragile X-associated primary ovarian insufficiency (FXPOI) is among the family of disorders caused by the expansion of a CGG repeat sequence in the 5' untranslated region of the X-linked gene FMR1. About 20% of women who carry the premutation allele (55 to 200 unmethylated CGG repeats) develop hypergonadotropic hypogonadism and cease menstruating before age 40. Some proportion of those who are still cycling show hormonal profiles indicative of ovarian dysfunction. FXPOI leads to subfertility and an increased risk of medical conditions associated with early estrogen deficiency. Little progress has been made in understanding the etiology of this clinically significant disorder. Understanding the molecular mechanisms of FXPOI requires a detailed knowledge of ovarian FMR1 mRNA and FMRP's function. In humans, non-invasive methods to discriminate the mechanisms of the premutation on ovarian function are not available, thus necessitating the development of model systems. Vertebrate (mouse and rat) and invertebrate (Drosophila melanogaster) animal studies for the FMR1 premutation and ovarian function exist and have been instrumental in advancing our understanding of the disease phenotype. For example, rodent models have shown that FMRP is highly expressed in oocytes where it is important for folliculogenesis. The two premutation mouse models studied to date show evidence of ovarian dysfunction and, together, suggest that the long repeat in the transcript itself may have some pathological effect quite apart from any effect of the toxic protein. Further, ovarian morphology in young animals appears normal and the primordial follicle pool size does not differ from that of wild-type animals. However, there is a progressive premature decline in the levels of most follicle classes. Observations also include granulosa cell abnormalities and altered gene expression patterns. Further comparisons of these models are now needed to gain insight into the etiology of the ovarian dysfunction. Premutation model systems in non-human primates and those based on induced pluripotent stem cells show particular promise and will complement current models. Here, we review the characterization of the current models and describe the development and potential of the new models. Finally, we will discuss some of the molecular mechanisms that might be responsible for FXPOI.
- Published
- 2014
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