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Most species-climate models relate range margins to long-term mean climate but lack mechanistic understanding of the ecological or demographic processes underlying the climate response. We examined the case of a climatically limited edge-of-range population of a medium-sized grassland bird, for which climate responses may involve a behavioural trade-off between temperature stress and reproduction. We hypothesised that temperature will be a limiting factor for the conspicuous, male snort-call display behaviour, and high temperatures would reduce the display activity of male birds. Using remote tracking technology with tri-axial accelerometers we classified and studied the display behaviour of 17 free-ranging male little bustards, Tetrax tetrax, at 5 sites in the Iberian Peninsula. Display behaviour was related to temperature using two classes of Generalized Additive Mixed Models (GAMMs) at different temporal resolutions. GAMMs showed that temperature, time of the day and Julian date explained variation in display behaviour within the day, with birds snort-calling significantly less during higher temperatures. We also showed that variation in daily snort-call activity was related to average daytime temperatures, with our model predicting an average decrease in daytime snort-call display activity of up to 10.4% for the temperature increases projected by 2100 in this region due to global warming. For lekking birds and mammals undertaking energetically-costly displays in a warming climate, reduced display behaviour could impact inter- and intra-sex mating behaviour interactions through sexual selection and mate choice mechanisms, with possible consequences on mating and reproductive success. The study provides a reproducible example for how accelerometer data can be used to answer research questions with important conservation inferences related to the impacts of climate change on a range of taxonomic groups.

Accurate chromosome segregation requires the attachment of microtubules to centromeres, epigenetically defined by the enrichment of CENP-A nucleosomes. During DNA replication, CENP-A nucleosomes undergo dilution. To preserve centromere identity, correct amounts of CENP-A must be restored in a cell cycle-controlled manner orchestrated by the Mis18 complex (Mis18α-Mis18β-Mis18BP1). We demonstrate here that PLK1 interacts with the Mis18 complex by recognizing self-primed phosphorylations of Mis18α (Ser 54 ) and Mis18BP1 (Thr 78 and Ser 93 ) through its Polo-box domain. Disrupting these phosphorylations perturbed both centromere recruitment of the CENP-A chaperone HJURP and new CENP-A loading. Biochemical and functional analyses showed that phosphorylation of Mis18α and PLK1 binding were required to activate Mis18α-Mis18β and promote Mis18 complex-HJURP interaction. Thus, our study reveals key molecular events underpinning the licensing role of PLK1 in ensuring accurate centromere inheritance.

The centromere, defined by the enrichment of CENP-A (a Histone H3 variant) containing nucleosomes, is a specialised chromosomal locus that acts as a microtubule attachment site. To preserve centromere identity, CENP-A levels must be maintained through active CENP-A loading during the cell cycle. A central player mediating this process is the Mis18 complex (Mis18α, Mis18β and Mis18BP1), which recruits the CENP-A-specific chaperone HJURP to centromeres for CENP-A deposition. Here, using a multi-pronged approach, we characterise the structure of the Mis18 complex and show that multiple hetero- and homo-oligomeric interfaces facilitate the hetero-octameric Mis18 complex assembly composed of 4 Mis18α, 2 Mis18β and 2 Mis18BP1. Evaluation of structure-guided/separation-of-function mutants reveals structural determinants essential for cell cycle controlled Mis18 complex assembly and centromere maintenance. Our results provide new mechanistic insights on centromere maintenance, highlighting that while Mis18α can associate with centromeres and deposit CENP-A independently of Mis18β, the latter is indispensable for the optimal level of CENP-A loading required for preserving the centromere identity., (© 2024. The Author(s).)

During mitosis, interphase chromatin is rapidly converted into rod-shaped mitotic chromosomes. Using Hi-C, imaging, proteomics and polymer modeling, we determine how the activity and interplay between loop-extruding SMC motors accomplishes this dramatic transition. Our work reveals rules of engagement for SMC complexes that are critical for allowing cells to refold interphase chromatin into mitotic chromosomes. We find that condensin disassembles interphase chromatin loop organization by evicting or displacing extrusive cohesin. In contrast, condensin bypasses cohesive cohesins, thereby maintaining sister chromatid cohesion while separating the sisters. Studies of mitotic chromosomes formed by cohesin, condensin II and condensin I alone or in combination allow us to develop new models of mitotic chromosome conformation. In these models, loops are consecutive and not overlapping, implying that condensins do not freely pass one another but stall upon encountering each other. The dynamics of Hi-C interactions and chromosome morphology reveal that during prophase loops are extruded in vivo at ~1-3 kb/sec by condensins as they form a disordered discontinuous helical scaffold within individual chromatids., Competing Interests: Competing interests: J.D. is a member of the advisory board of Arima Genomics (San Diego, CA, USA) and Omega Therapeutics (Cambridge, MA, USA). Other authors declare no competing interests.

Background: Unicorn™ software on Äkta liquid chromatography instruments outputs chromatography profiles of purified biological macromolecules. While the plots generated by the instrument software are very helpful to inspect basic chromatogram properties, they lack a range of useful annotation, customization and export options., Methods: We use the R Shiny framework to build an interactive app that facilitates the interpretation of chromatograms and the generation of figures for publications., Results: The app allows users to fit a baseline, to highlight selected fractions and elution volumes inside or under the plot (e.g. those used for downstream biochemical/biophysical/structural analysis) and to zoom into the plot. The app is freely available at https://ChromatoShiny.bio.ed.ac.uk., Conclusions: It requires no programming experience, so we anticipate that it will enable chromatography users to create informative, annotated chromatogram plots quickly and simply., Competing Interests: No competing interests were disclosed., (Copyright: © 2024 Kochanova NY et al.)

SPOUT1/CENP-32 encodes a putative SPOUT RNA methyltransferase previously identified as a mitotic chromosome associated protein. SPOUT1/CENP-32 depletion leads to centrosome detachment from the spindle poles and chromosome misalignment. Aided by gene matching platforms, we identified 24 individuals with neurodevelopmental delays from 18 families with bi-allelic variants in SPOUT1/CENP-32 detected by exome/genome sequencing. Zebrafish spout1/cenp-32 mutants showed reduction in larval head size with concomitant apoptosis likely associated with altered cell cycle progression. In vivo complementation assays in zebrafish indicated that SPOUT1/CENP-32 missense variants identified in humans are pathogenic. Crystal structure analysis of SPOUT1/CENP-32 revealed that most disease-associated missense variants mapped to the catalytic domain. Additionally, SPOUT1/CENP-32 recurrent missense variants had reduced methyltransferase activity in vitro and compromised centrosome tethering to the spindle poles in human cells. Thus, SPOUT1/CENP-32 pathogenic variants cause an autosomal recessive neurodevelopmental disorder: SpADMiSS ( SPOUT1 Associated Development delay Microcephaly Seizures Short stature) underpinned by mitotic spindle organization defects and consequent chromosome segregation errors.

Increased nuclear size correlates with lower survival rates and higher grades for prostate cancer. The short-chain dehydrogenase/reductase (SDR) family member DHRS7 was suggested as a biomarker for use in prostate cancer grading because it is largely lost in higher-grade tumors. Here, we found that reduction in DHRS7 from the LNCaP prostate cancer cell line with normally high levels of DHRS7 increases nuclear size, potentially explaining the nuclear size increase observed in higher-grade prostate tumors where it is lost. An exogenous expression of DHRS7 in the PC3 prostate cancer cell line with normally low DHRS7 levels correspondingly decreases nuclear size. We separately tested 80 compounds from the Microsource Spectrum library for their ability to restore normal smaller nuclear size to PC3 cells, finding that estradiol propionate had the same effect as the re-expression of DHRS7 in PC3 cells. However, the drug had no effect on LNCaP cells or PC3 cells re-expressing DHRS7. We speculate that separately reported beneficial effects of estrogens in androgen-independent prostate cancer may only occur with the loss of DHRS7/ increased nuclear size, and thus propose DHRS7 levels and nuclear size as potential biomarkers for the likely effectiveness of estrogen-based treatments.

Kinetochore protein phosphorylation promotes the correction of erroneous microtubule attachments to ensure faithful chromosome segregation during cell division. Determining how phosphorylation executes error correction requires an understanding of whether kinetochore substrates are completely (i.e., all-or-none) or only fractionally phosphorylated. Using quantitative mass spectrometry (MS), we measured phospho-occupancy on the conserved kinetochore protein Hec1 (NDC80) that directly binds microtubules. None of the positions measured exceeded ∼50% phospho-occupancy, and the cumulative phospho-occupancy changed by only ∼20% in response to changes in microtubule attachment status. The narrow dynamic range of phospho-occupancy is maintained, in part, by the ongoing phosphatase activity. Further, both Cdk1-Cyclin B1 and Aurora kinases phosphorylate Hec1 to enhance error correction in response to different types of microtubule attachment errors. The low inherent phospho-occupancy promotes microtubule attachment to kinetochores while the high sensitivity of kinetochore-microtubule attachments to small changes in phospho-occupancy drives error correction and ensures high mitotic fidelity., (© 2022 Kucharski et al.)

Centromere association of the chromosomal passenger complex (CPC; Borealin-Survivin-INCENP-Aurora B) and Sgo1 is crucial for chromosome biorientation, a process essential for error-free chromosome segregation. Phosphorylated histone H3 Thr3 (H3T3ph; directly recognized by Survivin) and histone H2A Thr120 (H2AT120ph; indirectly recognized via Sgo1), together with CPC's intrinsic nucleosome-binding ability, facilitate CPC centromere recruitment. However, the molecular basis for CPC-Sgo1 binding and how their physical interaction influences CPC centromere localization are lacking. Here, using an integrative structure-function approach, we show that the "histone H3-like" Sgo1 N-terminal tail-Survivin BIR domain interaction acts as a hotspot essential for CPC-Sgo1 assembly, while downstream Sgo1 residues and Borealin contribute for high-affinity binding. Disrupting Sgo1-Survivin interaction abolished CPC-Sgo1 assembly and perturbed CPC centromere localization and function. Our findings reveal that Sgo1 and H3T3ph use the same surface on Survivin to bind CPC. Hence, it is likely that these interactions take place in a spatiotemporally restricted manner, providing a rationale for the Sgo1-mediated "kinetochore-proximal" CPC centromere pool., (© 2022 Abad et al.)

Objectives: The objective of this non-interventional study was to evaluate the effectiveness and safety of the etanercept biosimilar SB4 (BenepaliTM) following transition from reference etanercept in patients with rheumatoid arthritis (RA) or axial spondyloarthritis (axSpA)., Methods: Data were collected from clinical records of adult patients with stable RA or axSpA, in France, Germany, Italy and Spain. Key outcomes included the change from transition to 3 and 6 months in Disease Activity Score 28 (DAS28) for RA or Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) for axSpA., Results: In total, 358 patients with RA and 199 patients with axSpA were enrolled. The mean individual change in disease score from transition was -0.02 (95% confidence interval [CI] -0.11, 0.08) at 3 months and 0.01 (95% CI -0.09, 0.11) at 6 months for DAS28, and -0.01 (95% CI -0.24, 0.21) at 3 months and -0.11 (95% CI -0.31, 0.10) at 6 months for BASDAI. In the RA cohort, 19 (5.3%) and 5 patients (1.4%) reported adverse events and serious adverse events (SAEs), respectively. In the axSpA cohort, 12 (6.0%) and 2 patients (1.0%) reported adverse events and SAEs, respectively. One SAE of pneumonia (RA cohort) was considered to be related to SB4 administration. At 6 months post-transition, the SB4 retention rate was 90.8% (95% CI 87.2%, 93.4%) in the RA cohort and 92.4% (95% CI 87.5%, 95.4%) in the axSpA cohort., Conclusions: Transition from reference etanercept to SB4 is effective and safe in patients with stable RA and axSpA.

Aneuploidy, the gain or loss of chromosomes in a cell, is a hallmark of cancer. Although our understanding of the contribution of aneuploidy to cancer initiation and progression is incomplete, significant progress has been made in uncovering the cellular consequences of aneuploidy and how aneuploid cancer cells self-adapt to promote tumorigenesis. Aneuploidy is physiologically associated with significant cellular stress but, paradoxically, it favors tumor progression. Although more common in solid tumors, different forms of aneuploidy represent the initiating oncogenic lesion in patients with B cell acute lymphoblastic leukemia (B-ALL), making B-ALL an excellent model for studying the role of aneuploidy in tumorigenesis. We review the molecular mechanisms underlying aneuploidy and discuss its contributions to B-ALL initiation and progression., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Human artificial chromosomes (HACs) are important tools for epigenetic engineering, for measuring chromosome instability (CIN), and for possible gene therapy. However, their use in the latter is potentially limited because the input HAC-seeding DNA can undergo an unpredictable series of rearrangements during HAC formation. As a result, after transfection and HAC formation, each cell clone contains a HAC with a unique structure that cannot be precisely predicted from the structure of the HAC-seeding DNA. Although it has been reported that these rearrangements can happen, the timing and mechanism of their formation has yet to be described. Here we synthesized a HAC-seeding DNA with two distinct structural domains and introduced it into HT1080 cells. We characterized a number of HAC-containing clones and subclones to track DNA rearrangements during HAC establishment. We demonstrated that rearrangements can occur early during HAC formation. Subsequently, the established HAC genomic organization is stably maintained across many cell generations. Thus, early stages in HAC formation appear to at least occasionally involve a process of DNA shredding and shuffling that resembles chromothripsis, an important hallmark of many cancer types. Understanding these events during HAC formation has critical implications for future efforts aimed at synthesizing and exploiting synthetic human chromosomes.

The identification of modulators for proteins without assayable biochemical activity remains a challenge in chemical biology. The presented approach adapts a high-throughput fluorescence binding assay and functional chromatography, two protein-resin technologies, enabling the discovery and isolation of fluorescent natural product probes that target proteins independently of biochemical function. The resulting probes also suggest targetable pockets for lead discovery. Using human survivin as a model, we demonstrate this method with the discovery of members of the prodiginine family as fluorescent probes to the cancer target survivin., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Objectives: 1) To systematically and critically review the evidence on the characteristics, efficacy and safety of glucocorticoids (CS) in rheumatoid arthritis (RA); 2) to generate practical recommendations., Methods: A systematic literature review was performed through a sensitive bibliographic search strategy in Medline, Embase and the Cochrane Library. We selected randomized clinical trials that analyzed the efficacy and/or safety of CS in patients with RA. Two reviewers performed the first selection by title and abstract. Then 10 reviewers selected the studies after a detailed review of the articles and data collection. The quality of the studies was evaluated with the Jadad scale. In a nominal group meeting, based on the results of the systematic literature review, related recommendations were reached by consensus., Results: A total of 47 articles were finally included. CS in combination with disease-modifying antirheumatic drugs help control disease activity and inhibit radiographic progression, especially in the short-to-medium term and in early RA. CS can also improve function and relieve pain. Different types and routes of administration are effective, but there is no standardized scheme (initial dose, tapering and duration of treatment) that is superior to others. Adverse events when using CS are very frequent and are dose-dependent and variable severity, although most are mild. Seven recommendations were generated on the use and risk management of CS., Conclusions: These recommendations aim to resolve some common clinical questions and aid in decision-making for CS use in RA., (Copyright © 2018 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.)

Centromeres are microtubule attachment sites on chromosomes defined by the enrichment of histone variant CENP-A-containing nucleosomes. To preserve centromere identity, CENP-A must be escorted to centromeres by a CENP-A-specific chaperone for deposition. Despite this essential requirement, many eukaryotes differ in the composition of players involved in centromere maintenance, highlighting the plasticity of this process. In humans, CENP-A recognition and centromere targeting are achieved by HJURP and the Mis18 complex, respectively. Using X-ray crystallography, we here show how Drosophila CAL1, an evolutionarily distinct CENP-A histone chaperone, binds both CENP-A and the centromere receptor CENP-C without the requirement for the Mis18 complex. While an N-terminal CAL1 fragment wraps around CENP-A/H4 through multiple physical contacts, a C-terminal CAL1 fragment directly binds a CENP-C cupin domain dimer. Although divergent at the primary structure level, CAL1 thus binds CENP-A/H4 using evolutionarily conserved and adaptive structural principles. The CAL1 binding site on CENP-C is strategically positioned near the cupin dimerisation interface, restricting binding to just one CAL1 molecule per CENP-C dimer. Overall, by demonstrating how CAL1 binds CENP-A/H4 and CENP-C, we provide key insights into the minimalistic principles underlying centromere maintenance., (© 2020 The Authors. Published under the terms of the CC BY 4.0 license.)

Chromosome association of the chromosomal passenger complex (CPC; consisting of Borealin, Survivin, INCENP, and the Aurora B kinase) is essential to achieve error-free chromosome segregation during cell division. Hence, understanding the mechanisms driving the chromosome association of the CPC is of paramount importance. Here using a multifaceted approach, we show that the CPC binds nucleosomes through a multivalent interaction predominantly involving Borealin. Strikingly, Survivin, previously suggested to target the CPC to centromeres, failed to bind nucleosomes on its own and requires Borealin and INCENP for its binding. Disrupting Borealin-nucleosome interactions excluded the CPC from chromosomes and caused chromosome congression defects. We also show that Borealin-mediated chromosome association of the CPC is critical for Haspin- and Bub1-mediated centromere enrichment of the CPC and works upstream of the latter. Our work thus establishes Borealin as a master regulator determining the chromosome association and function of the CPC., (© 2019 Abad et al.)

Objective: To examine the grade of agreement between very low disease activity (VLDA) and Disease Activity Index for Psoriatic Arthritis (DAPSA) remission, as well as their association with the effect of the disease as assessed by the Psoriatic Arthritis Impact of Disease (PsAID) questionnaire in patients with psoriatic arthritis in routine clinical practice., Methods: Posthoc analysis of data from a cross-sectional multicenter study. Patients were included who fulfilled the Classification for Psoriatic Arthritis (CASPAR) criteria with at least 1 year of disease duration and were treated with biological and/or conventional synthetic disease-modifying antirheumatic drugs according to routine clinical practice in Spain. Patients were considered in VLDA if they met 7/7 of the minimal disease activity criteria. DAPSA and clinical (c)DAPSA score ≤ 4 identified remissions., Results: Of the 227 patients included in the original study, 26 (11.5%), 52 (22.9%), and 65 (28.6%) were in VLDA, DAPSA remission, and cDAPSA remission, respectively. There was a moderate agreement between VLDA and DAPSA remission (κ = 0.52) or cDAPSA remission (κ = 0.42). Patients with VLDA had less effect of the disease as measured by PsAID [mean total score (SD): VLDA 1.1 (1.2); DAPSA remission 1.3 (1.5); cDAPSA remission 1.7 (1.6)]. There was a moderate agreement between DAPSA remission or cDAPSA remission and PsAID < 4 (κ = 0.46 and κ = 0.58 respectively), while poor agreement (κ = 0.18) was found between VLDA and PsAID < 4., Conclusion: VLDA criteria seem to be more stringent for assessing a status of remission; however, DAPSA remission shows better correlation with a patient-acceptable symptoms state than VLDA does.

The endosomal sorting complex required for transport (ESCRT)-III proteins are known to assemble into filaments that mediate membrane remodeling and fission in various biological processes, including the formation of endosomal multivesicular bodies, viral budding, cytokinesis, plasma membrane repair, nuclear pore quality control, nuclear envelope reformation, and neuron pruning. The study of the regulation and function of ESCRT-III proteins is therefore crucial to understand these events and requires a combination of in vivo and in vitro experimental techniques. Here we describe two protocols for the purification of human and Drosophila ESCRT-III proteins from bacteria and their use in in vitro phosphorylation assays and atomic force microscopy experiments on membrane lipid bilayers. These protocols can also be applied for the purification of other proteins that are insoluble when expressed in bacteria.

Spontaneous regression of a primary testicular germ-cell tumour (GCT), over time known as 'Burned out', 'Shrinking Seminoma', 'pT0', 'Burnout' or 'Spontaneous Regression', is an uncommon, generally metastatic phenomenon, which may present elevated tumour markers and a suspicious testicular ultrasound image. The histological study of the testicle demonstrated morphological changes of complete or partial tumour regression and found fibrous scarring and other characteristic changes of this phenomenon, which in some cases include vestiges of GCT. There are few publications on testicular GCT tumour regression and those that exist present limited data on the biology of the disease and its etiopathogenesis. This entity was recently recognised in the latest edition of the World Health Organization's (WHO) Classification of Tumours. We present our clinical, imaging, laboratory, cytohistological and management experience, as well as a historical review of the literature.

The role of a 32 base pair deletion in the CCR5 gene (CCR5Δ32) in HIV-disease progression and response to combined antiretroviral therapy (cART) is well established. However, the impact of CCR5Δ32 in the long-term survival pre-cART and after cART introduction in a large cohort of HIV-infected patients is unknown. We analyzed the association of CCR5Δ32 deletion in the long-term survival of HIV-infected patients recruited between June 1981 and October 2016 (n = 1006). Clinical and epidemiological variables were recorded and CCR5Δ32 deletion was assessed by PCR and electrophoretic analysis. The association of CCR5Δ32 deletion with the time to death was analyzed by Log-Rank tests and Cox Regression models. The CCR5 WT/Δ32 prevalence was 13.4% (n = 135). We did not find any homozygous subject for CCR5Δ32 deletion. AIDS (n = 85, 41.5%) and non-AIDS (n = 87, 42.4%) events were the main causes of 205 deaths. CCR5Δ32 deletion was independently associated with survival (p = 0.022; hazard ratio (HR): 0.572, confidence interval (CI) [0.354-0.923]), after adjusting by HIV diagnosis before 1997, age at diagnosis, being on cART, risk of transmission, nadir CD4 + T-cell counts and CDC stage C. This result was reproduced when the analysis was restricted to patients on cART (p = 0.045; HR: 0.530 [0.286-0.985]). These results confirm the protective role of CCR5Δ32, and extend it to the long-term survival in a large cohort of HIV-infected patients. Beyond its antiviral effect, CCR5Δ32 enhanced the long-term survival of patients on cART., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objectives: Inflammatory arthritis needs infectious disease screening before starting a biologic agent, however, few data are known about migrant patients, who represent a peculiar population which requires a multidisciplinary approach among international health specialists and should also be considered by health authorities. For this reason, the Italian and Spanish Societies of Rheumatology (SIR and SER) and Tropical Medicine (SIMET and SEMTSI) promoted a multidisciplinary task force in order to produce specific recommendations about screening and advices to be considered in migrant patients with inflammatory arthritis candidate to receive biological therapy, according to their geographical origin., Methods: The experts provided a prioritised list of research questions and the eligible spectrum of inflammatory arthritis, biologic drugs and infectious disease were defined in order to perform a systematic literature review. A search was made in Medline, Embase and Cochrane library, updated to March 2015. Ubiquitous infections and HBV, HCV, HIV and tuberculosis that are already considered in national and international recommendations, were not included. The strength of each recommendation was determined., Results: The task force members agreed on 7 overarching principles. The risk of reactivation of selected potentially latent infectious disease was addressed in migrants with inflammatory arthritis candidates for biologics was considered and 15 potentially relevant infections were identified., Conclusions: Fifteen disease-specific recommendations were formulated on the basis of high level of agreement among the experts panel.

We explored if baseline CD4/CD8 T-cell ratio is associated with immunodiscordant response to antiretroviral therapy in HIV-infected subjects. Comparing immunodiscordant and immunoconcordant subjects matched by pretreatment CD4 counts, we observed a lower pretreatment CD4/CD8 T-cell ratio in immunodiscordant subjects. Furthermore, pretreatment CD4/CD8 T-cell ratio, but not CD4 counts, correlated with the main immunological alterations observed in immunodiscordants, including increased regulatory T-cell (Treg) frequency and T-cell turnover-related markers. Then, in a larger cohort, only baseline CD4/CD8 T-cell ratio was independently associated with immunodiscordance, after adjusting by the viral CXCR4-tropic HIV variants. Our results suggest that the CD4/CD8 T-cell ratio could be an accurate biomarker of the subjacent immunological damage triggering immunodiscordance., (Copyright © 2017 American Society for Microbiology.)

The centromere, a chromosomal locus that acts as a microtubule attachment site, is epigenetically specified by the enrichment of CENP-A nucleosomes. Centromere maintenance during the cell cycle requires HJURP-mediated CENP-A deposition, a process regulated by the Mis18 complex (Mis18α/Mis18β/Mis18BP1). Spatial and temporal regulation of Mis18 complex assembly is crucial for its centromere association and function. Here, we provide the molecular basis for the assembly and regulation of the Mis18 complex. We show that the N-terminal region of Mis18BP1 spanning amino acid residues 20-130 directly interacts with Mis18α/β to form the Mis18 complex. Within Mis18α/β, the Mis18α MeDiY domain can directly interact with Mis18BP1. Mis18α/β forms a hetero-hexamer with 4 Mis18α and 2 Mis18β. However, only two copies of Mis18BP1 interact with Mis18α/β to form a hetero-octameric assembly, highlighting the role of Mis18 oligomerization in limiting the number of Mis18BP1 within the Mis18 complex. Furthermore, we demonstrate the involvement of consensus Cdk1 phosphorylation sites on Mis18 complex assembly and thus provide a rationale for cell cycle-regulated timing of Mis18 assembly and CENP-A deposition., (© 2017 The Authors. Published under the terms of the CC BY 4.0 license.)

Centromeres consist of specialized centrochromatin containing CENP-A nucleosomes intermingled with H3 nucleosomes carrying transcription-associated modifications. We have designed a novel synthetic biology 'in situ epistasis' analysis in which H3 dimethylated on lysine 4 (H3K4me2) demethylase LSD2 plus synthetic modules with competing activities are simultaneously targeted to a synthetic alphoid tetO HAC centromere. This allows us to uncouple transcription from histone modifications at the centromere. Here, we report that H3K4me2 loss decreases centromeric transcription, CENP-A assembly and stability and causes spreading of H3K9me3 across the HAC, ultimately inactivating the centromere. Surprisingly, CENP-28/Eaf6-induced transcription of the alphoid tetO array associated with H4K12 acetylation does not rescue the phenotype, whereas p65-induced transcription associated with H3K9 acetylation does rescue. Thus mitotic transcription plus histone modifications including H3K9ac constitute the 'epigenetic landscape' allowing CENP-A assembly and centrochromatin maintenance. H3K4me2 is required for the transcription and H3K9ac may form a barrier to prevent heterochromatin spreading and kinetochore inactivation at human centromeres.

The chromosomal passenger complex (CPC)-composed of Aurora B kinase, Borealin, Survivin and INCENP-surveys the fidelity of genome segregation throughout cell division. The CPC has been proposed to prevent polyploidy by controlling the final separation (known as abscission) of the two daughter cells via regulation of the ESCRT-III CHMP4C component. The molecular details are, however, still unclear. Using atomic force microscopy, we show that CHMP4C binds to and remodels membranes in vitro Borealin prevents the association of CHMP4C with membranes, whereas Aurora B interferes with CHMP4C's membrane remodelling activity. Moreover, we show that CHMP4C phosphorylation is not required for its assembly into spiral filaments at the abscission site and that two distinctly localized pools of phosphorylated CHMP4C exist during cytokinesis. We also characterized the CHMP4C interactome in telophase cells and show that the centralspindlin complex associates preferentially with unphosphorylated CHMP4C in cytokinesis. Our findings indicate that gradual dephosphorylation of CHMP4C triggers a 'relay' mechanism between the CPC and centralspindlin that regulates the timely distribution and activation of CHMP4C for the execution of abscission., (© 2016 The Authors.)

The establishment of physical attachment between the kinetochore and dynamic spindle microtubules, which undergo cycles of polymerization and depolymerization generating straight and curved microtubule structures, is essential for accurate chromosome segregation. The Ndc80 and Ska complexes are the major microtubule-binding factors of the kinetochore responsible for maintaining chromosome-microtubule coupling during chromosome segregation. We previously showed that the Ska1 subunit of the Ska complex binds dynamic microtubules using multiple contact sites in a mode that allows conformation-independent binding. Here, we show that the Ska3 subunit is required to modulate the microtubule binding capability of the Ska complex (i) by directly interacting with tubulin monomers and (ii) indirectly by interacting with tubulin contacting regions of Ska1 suggesting an allosteric regulation. Perturbing either the Ska3-microtubule interaction or the Ska3-Ska1 interactions negatively influences microtubule binding by the Ska complex in vitro and affects the timely onset of anaphase in cells. Thus, Ska3 employs additional modulatory elements within the Ska complex to ensure robust kinetochore-microtubule attachments and timely progression of mitosis.

Background: Glucocorticoid (GC) therapy is associated with an increased risk of fractures. The main objective of this study was to determine the prevalence of undiagnosed vertebral fractures in women chronically using GC therapy for autoimmune disorders. We also determined the prevalence of non-vertebral fractures, and investigated whether factors such as quality-of-life and future fracture risk are associated with vertebral/non-vertebral fractures., Methods: This was a multicenter cross-sectional study conducted in Spain. All women had rheumatoid arthritis (RA) and/or systemic lupus erythematosus (SLE). Radiological morphometric vertebral fractures were evaluated centrally (Genant semiquantitative method), whereas non-vertebral fractures were not assessed by radiography. Before radiography, patients were asked whether they had vertebral/non-vertebral fractures, hereafter referred to as 'self-reported' fractures. Assessment tools included the Disease Activity Score (DAS28), the SF-36 questionnaire, and FRAX®., Results: Complete data were obtained for 576 outpatients with RA and/or SLE (83.3 % had RA); mean [SD] age 59.6 [15] years. Of all patients, 6.4 % had self-reported vertebral fractures, whereas 18.9 % had morphometric vertebral fractures (RA: 7.1 % self-reported vs. 20.0 % morphometric; SLE: 3.2 % self-reported vs. 13.7 % morphometric). Non-vertebral fractures were self-reported by 9.8 % of RA and 5.3 % of SLE patients. Low physical functioning was associated with morphometric vertebral fractures (mean [SD] SF-36 score 18.8 [6.0] when present vs. 20.1 [5.9] when absent; p = 0.028) and self-reported non-vertebral fractures (16.7 [5.2] when present vs. 20.1 [5.9] when absent; p < 0.001). Mean [SD] DAS28 was higher (p = 0.013) when any self-reported fractures were present (4.0 [1.3]) than absent (3.6 [1.3]). Based on FRAX® analysis, patients with vs. without morphometric vertebral fractures had higher 10-year probabilities of major osteoporotic fractures (mean [SD] 17.9 [12.9]% vs. 9.9 [9.6]%; p < 0.001) and hip fractures (11.0 [11.7]% vs. 4.6 [8.1]%; p < 0.001)., Conclusions: Morphometric vertebral fractures were detected in 18.9 % of patients, i.e. 3-times more frequently than verbally reported by patients. Patients with vs. without fractures had worse quality-of-life and increased fracture risk. Accordingly, it is of utmost importance that women chronically using GCs are assessed for fractures, including morphometric vertebral fractures.

Our aim was to analyze the virological response to a combined antiretroviral therapy started after Maraviroc Clinical Test (MCT) in naïve HIV-infected patients. Forty-one patients were exposed to MCT, based on an 8-day MVC monotherapy. If undetectability or a viral load reduction >1 log10 HIV-RNA copies/ml was achieved, a MVC-containing cART was prescribed. Forty patients showed a positive MCT; undetectability after 48weeks on cART was achieved in 34/41 (82.9%) patients. The result of MCT was compared with a genotypic tropism method and with Trofile®, showing 10.7% and 18.75% discordance rates, respectively. MCT is a reliable tool to decide CCR5-antagonists prescription, also in the naïve scenario where most patients show a virological response to MVC independently the tropism result reported by genotypic or phenotypic methods., (Copyright © 2015 Elsevier B.V. All rights reserved.)

TD-60 (also known as RCC2) is a highly conserved protein that structurally resembles the Ran guanine exchange factor (GEF) RCC1, but has not previously been shown to have GEF activity. TD-60 has a typical chromosomal passenger complex (CPC) distribution in mitotic cells, but associates with integrin complexes and is involved in cell motility during interphase. Here we show that TD-60 exhibits GEF activity, in vitro and in cells, for the small GTPase RalA. TD-60 or RalA depletion causes spindle abnormalities in prometaphase associated with abnormal centromeric accumulation of CPC components. TD-60 and RalA apparently work together to contribute to the regulation of kinetochore-microtubule interactions in early mitosis. Importantly, several mitotic phenotypes caused by TD-60 depletion are reverted by the expression of a GTP-locked mutant, RalA (Q72L). The demonstration that a small GTPase participates in the regulation of the CPC reveals a level of mitotic regulation not suspected in previous studies.

In mature neurons, the number of synapses is determined by a neuronal activity-dependent dynamic equilibrium between positive and negative regulatory factors. We hypothesized that neuronal pentraxin (NP1), a proapoptotic protein induced by low neuronal activity, could be a negative regulator of synapse density because it is found in dystrophic neurites in Alzheimer's disease-affected brains. Here, we report that knockdown of NP1 increases the number of excitatory synapses and neuronal excitability in cultured rat cortical neurons and enhances excitatory drive and long-term potentiation in the hippocampus of behaving mice. Moreover, we found that NP1 regulates the surface expression of the Kv7.2 subunit of the Kv7 family of potassium channels that control neuronal excitability. Furthermore, pharmacological activation of Kv7 channels prevents, whereas inhibition mimics, the increase in synaptic proteins evoked by the knockdown of NP1. These results indicate that NP1 negatively regulates excitatory synapse number by modulating neuronal excitability and show that NP1 restricts excitatory synaptic plasticity., (Copyright © 2015 the authors 0270-6474/15/355504-18$15.00/0.)

Novel strategies are necessary to decrease inflammatory parameters in successfully treated HIV-infected patients. Our aim was to evaluate the maintenance of viral suppression and potential changes in inflammatory, immune-activation and coagulation biomarkers in virologically suppressed HIV-infected patients switched to a nucleoside reverse transcriptase inhibitor-sparing (NRTI) and maraviroc (MVC)-containing combined antiretroviral therapy (cART). Fifty-eight HIV-infected patients were observed after their treatment regimens were changed to MVC 150mg/once daily plus ritonavir-boosted protease inhibitor therapy. Activation-, inflammation- and coagulation-associated biomarkers and mitochondrial (mt)DNA were analyzed after a median of 24weeks of follow-up. We observed that after changing to an NRTI-sparing regimen, 96.6% of HIV-patients on viral suppressive cART maintained viral suppression and their CD4+ T cell counts did not change significantly (median of 31weeks of follow-up). This cART switch reduced soluble CD40 ligand (p=0.002), beta-2 microglobulin (p=0.025), and soluble CD14 (p=0.009) in patients with higher baseline levels of these inflammation biomarkers after a median of 24weeks of follow-up. The results of our study show that changing to NRTI-sparing dual therapy decreased the levels of inflammatory biomarkers and maintained the immune-virologic efficacy. The potential benefits of this regimen warrant further investigation to uncover the association of this therapy with the potential decrease in the morbidity and mortality of HIV-infected patients from non-AIDS-defining illnesses., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The ability of kinetochores (KTs) to maintain stable attachments to dynamic microtubule structures ('straight' during microtubule polymerization and 'curved' during microtubule depolymerization) is an essential requirement for accurate chromosome segregation. Here we show that the kinetochore-associated Ska complex interacts with tubulin monomers via the carboxy-terminal winged-helix domain of Ska1, providing the structural basis for the ability to bind both straight and curved microtubule structures. This contrasts with the Ndc80 complex, which binds straight microtubules by recognizing the dimeric interface of tubulin. The Ska1 microtubule-binding domain interacts with tubulins using multiple contact sites that allow the Ska complex to bind microtubules in multiple modes. Disrupting either the flexibility or the tubulin contact sites of the Ska1 microtubule-binding domain perturbs normal mitotic progression, explaining the critical role of the Ska complex in maintaining a firm grip on dynamic microtubules.

The single-nucleotide polymorphism (SNP) rs12979860 near the IL28B gene has been associated with the spontaneous clearance of hepatitis C virus. We sought to determine whether this SNP could be associated with the spontaneous control of human immunodeficiency virus (HIV) infection. We studied the prevalence of the IL28B CC genotype among 53 white HIV controllers, compared with the prevalence among 389 HIV-infected noncontrollers. We found that the IL28B CC genotype was independently associated with spontaneous HIV control (odds ratio [OR], 2.669; P = .017), as were female sex (OR, 7.077; P ≤ .001) and the presence of HLA-B57 and/or B27 (OR, 3.080; P = .017). This result supports the idea that common host mechanisms are involved in the spontaneous control of these 2 chronic infections.

Background: Transtheoretical model is identified as a comprehensive model for behavior exercise. The aim of this study was to check the situation of stage of change in exercise behavior of office personnel of Yazd city using transtheoretical model., Methods: In a cross-sectional study, 220 office personnel selected from administrative offices of Yazd through two-stage cluster-sampling method. The instrument for data collection was a questionnaire that included demographic variables and constructs of transtheoretical model. The reliability and validity of the instruments were examined and approved by experts. The data was analyzed using SPSS soft ware., Results: 152 males (69.1%) and 68 females (30.9%) with an average age of 34±8.68 years were selected. Sixty percent of the subjects were in precontemplation and contemplation stages and only 7.3% were in action stages. Significant differences were found between TTM constructs and stages of change (P=0.000). The results also showed significant differences between components of decisional balance and behavioral process and cognitive process with the stages of change. We found that behavioral process of change and self efficacy were the most important variables for improving levels of exercise., Conclusion: Most of the participants were in the precontemplation and contemplation stages and most problems were related to behavioral process and self efficacy. Therefore, strategies and programs are needed to be taken into account to improve exercise among the staff.

To compare prevalence and risk factors associated with fear of falling (FoF) in two groups of elderly people, 109 patients with recurrent dizziness and 109 controls without dizziness. FoF was defined as a positive response to the single question and with Falls Efficacy Scale of >50. The prevalence of FoF was greater (71.6%) in the dizzy group (control, 31.2%; p<0.001). Factors associated with FoF in the dizzy-group were diabetes, high General Health Questionnaire (GHQ-28) score and poor balance score. In the non-dizzy group, female gender, high GHQ, and poor gait score in Tinetti's scale were the association. Further research is needed to explore the relationship between dizziness and FoF., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Peripheral nerve injury causes spontaneous and long-lasting pain, hyperalgesia, and allodynia. Excitatory amino acid receptor-dependent increases in descending facilitatory drive from the brainstem rostral ventromedial medulla (RVM) contribute to injury-evoked hypersensitivity. Although increased excitability likely reflects changes in synaptic efficacy, the cellular mechanisms underlying injury-induced synaptic plasticity are poorly understood. Neuronal pentraxin 1 (NP1), a protein with exclusive CNS expression, is implicated in synaptogenesis and AMPA receptor recruitment to immature synapses. Its role in the adult brain and in descending pain facilitation is unknown. Here, we use the spared nerve injury (SNI) model in rodents to examine this issue. We show that SNI increases RVM NP1 expression and constitutive deletion or silencing NP1 in the RVM, before or after SNI, attenuates allodynia and hyperalgesia in rats. Selective rescue of RVM NP1 expression restores behavioral hypersensitivity of knock-out mice, demonstrating a key role of RVM NP1 in the pathogenesis of neuropathic pain.

We analyzed the evolution of viral tropism after 8 days of maraviroc monotherapy, i.e., we used the maraviroc clinical test (MCT), in 21 patients with and 14 without virological response to the drug (MCT(+) and MCT(-) patients, respectively). No increases in CXCR4 inferred viral loads (X4IVLs) were observed in MCT(+) patients, while X4IVLs increased only in MCT(-) patients, with X4IVLs of >2 log(10) HIV RNA copies/ml. These results shed light on the evolution of viral tropism under a CCR5 antagonist in vivo.

Genotypic tropism testing methods are emerging as the first step before prescription of the CCR5 antagonist maraviroc (MVC) to HIV-infected patients in Europe. Studies validating genotypic tests have included other active drugs that could have potentially convoluted the effects of MVC. The maraviroc clinical test (MCT) is an in vivo drug sensitivity test based on the virological response to a short-term exposure to MVC monotherapy. Thus, our aim was to compare the results of genotypic tropism testing methods with the short-term virological response to MVC monotherapy. A virological response in the MCT was defined as a ≥ 1-log(10) decrease in HIV RNA or undetectability after 8 days of drug exposure. Seventy-three patients undergoing the MCT were included in this study. We used both standard genotypic methods (n = 73) and deep sequencing (n = 27) on MCT samples at baseline. For the standard methods, the most widely used genotypic algorithms for analyzing the V3 loop sequence, geno2pheno and PSSM, were used. For deep sequencing, the geno2pheno algorithm was used with a false-positive rate cutoff of 3.5. The discordance rates between the standard genotypic methods and the virological response were approximately 20% (including mostly patients without a virological response). Interestingly, these discordance rates were similar to that obtained from deep sequencing (18.5%). The discordance rates between the genotypic methods (tropism assays predictive of the use of the CCR5 coreceptor) and the MCT (in vivo MVC sensitivity assay) indicate that the algorithms used by genotypic methods are still not sufficiently optimized.