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Supplementary Figure 1 from Mitochondrial Chaperone Trap1 and the Calcium Binding Protein Sorcin Interact and Protect Cells against Apoptosis Induced by Antiblastic Agents

Supplementary Figure 3 from Mitochondrial Chaperone Trap1 and the Calcium Binding Protein Sorcin Interact and Protect Cells against Apoptosis Induced by Antiblastic Agents

Supplementary Figure 4 from Mitochondrial Chaperone Trap1 and the Calcium Binding Protein Sorcin Interact and Protect Cells against Apoptosis Induced by Antiblastic Agents

Supplementary Figure 1 from Chromobox Protein Homologue 7 Protein, with Decreased Expression in Human Carcinomas, Positively Regulates E-Cadherin Expression by Interacting with the Histone Deacetylase 2 Protein

Supplementary Figure 2 from Chromobox Protein Homologue 7 Protein, with Decreased Expression in Human Carcinomas, Positively Regulates E-Cadherin Expression by Interacting with the Histone Deacetylase 2 Protein

Chromobox protein homologue 7 (CBX7) is a chromobox family protein encoding a novel polycomb protein, the expression of which shows a progressive reduction, well related with the malignant grade of the thyroid neoplasias. Indeed, CBX7 protein levels decreased in an increasing percentage of cases going from benign adenomas to papillary, follicular, and anaplastic thyroid carcinomas. To elucidate the function of CBX7 in carcinogenesis, we searched for CBX7 interacting proteins by a proteomic analysis. By this approach, we identified several proteins. Among these proteins, we selected histone deacetylase 2 (HDAC2), which is well known to play a key role in neoplastic cell transformation and down-regulation of E-cadherin expression, the loss of which is a critical event in the epithelial-to-mesenchymal transition. We confirmed by coimmunoprecipitation that CBX7 physically interacts with the HDAC2 protein and is able to inhibit its activity. Then, we showed that both these proteins bind the E-cadherin promoter and that CBX7 up-regulates E-cadherin expression. Consistent with these data, we found a positive statistical correlation between CBX7 and E-cadherin expression in human thyroid carcinomas. Finally, we showed that the expression of CBX7 increases the acetylation status of the histones H3 and H4 on the E-cadherin promoter. Therefore, the ability of CBX7 to positively regulate E-cadherin expression by interacting with HDAC2 and inhibiting its activity on the E-cadherin promoter would account for the correlation between the loss of CBX7 expression and a highly malignant phenotype. [Cancer Res 2009;69(17):7079–87]

TRAP1, a mitochondrial chaperone (Hsp75) with antioxidant and antiapoptotic functions, is involved in multidrug resistance in human colorectal carcinoma cells. Through a proteomic analysis of TRAP1 coimmunoprecipitation complexes, the Ca2+-binding protein Sorcin was identified as a new TRAP1 interactor. This result prompted us to investigate the presence and role of Sorcin in mitochondria from human colon carcinoma cells. Using fluorescence microscopy and Western blot analysis of purified mitochondria and submitochondrial fractions, we showed the mitochondrial localization of an isoform of Sorcin with an electrophoretic motility lower than 20 kDa that specifically interacts with TRAP1. Furthermore, the effects of overexpressing or downregulating Sorcin and/or TRAP1 allowed us to demonstrate a reciprocal regulation between these two proteins and to show that their interaction is required for Sorcin mitochondrial localization and TRAP1 stability. Indeed, the depletion of TRAP1 by short hairpin RNA in colorectal carcinoma cells lowered Sorcin levels in mitochondria, whereas the depletion of Sorcin by small interfering RNA increased TRAP1 degradation. We also report several lines of evidence suggesting that intramitochondrial Sorcin plays a role in TRAP1 cytoprotection. Finally, preliminary evidence that TRAP1 and Sorcin are both implicated in multidrug resistance and are coupregulated in human colorectal carcinomas is provided. These novel findings highlight a new role for Sorcin, suggesting that some of its previously reported cytoprotective functions may be explained by involvement in mitochondrial metabolism through the TRAP1 pathway. Cancer Res; 70(16); 6577–86. ©2010 AACR.

Supplementary Figure Legends 1- 4 from Mitochondrial Chaperone Trap1 and the Calcium Binding Protein Sorcin Interact and Protect Cells against Apoptosis Induced by Antiblastic Agents

Supplementary Figure 2 from Mitochondrial Chaperone Trap1 and the Calcium Binding Protein Sorcin Interact and Protect Cells against Apoptosis Induced by Antiblastic Agents

Supplementary Figure Legends 1-2 from Chromobox Protein Homologue 7 Protein, with Decreased Expression in Human Carcinomas, Positively Regulates E-Cadherin Expression by Interacting with the Histone Deacetylase 2 Protein

Supplementary Methods from Chromobox Protein Homologue 7 Protein, with Decreased Expression in Human Carcinomas, Positively Regulates E-Cadherin Expression by Interacting with the Histone Deacetylase 2 Protein

Supplementary Table 1 from Mitochondrial Chaperone Trap1 and the Calcium Binding Protein Sorcin Interact and Protect Cells against Apoptosis Induced by Antiblastic Agents

Supplementary Table 1 from Chromobox Protein Homologue 7 Protein, with Decreased Expression in Human Carcinomas, Positively Regulates E-Cadherin Expression by Interacting with the Histone Deacetylase 2 Protein

The H Ferritin subunit (FTH1), as well as regulating the homeostasis of intracellular iron, is involved in complex pathways that might promote or inhibit carcinogenesis. This function may be mediated by its ability to interact with different molecules. To gain insight into the FTH1 interacting molecules, we analyzed its interactome in HEK293T cells. Fifty-one proteins have been identified, and among them, we focused our attention on a member of the peroxiredoxin family (PRDX6), an antioxidant enzyme that plays an important role in cell proliferation and in malignancy development. The FTH1/PRDX6 interaction was further supported by co-immunoprecipitation, in HEK293T and H460 cell lines and by means of computational methods. Next, we demonstrated that FTH1 could inhibit PRDX6-mediated proliferation and migration. Then, the results so far obtained suggested that the interaction between FTH1/PRDX6 in cancer cells might alter cell proliferation and migration, leading to a less invasive phenotype.

Arsenic detoxification systems can be found in a wide range of organisms, from bacteria to man. In a previous study, we discovered an arsenic-responsive transcriptional regulator in the thermophilic bacterium Thermus thermophilus HB27 (TtSmtB). Here, we characterize the arsenic resistance system of T. thermophilus in more detail. We employed TtSmtB-based pull-down assays with protein extracts from cultures treated with arsenate and arsenite to obtain an S-adenosyl-Lmethionine (SAM)-dependent arsenite methyltransferase (TtArsM). In vivo and in vitro analyses were performed to shed light on this new component of the arsenic resistance network and its peculiar catalytic mechanism. Heterologous expression of TtarsM in Escherichia coli resulted in arsenite detoxification at mesophilic temperatures. Although TtArsM does not contain a canonical arsenite binding site, the purified protein does catalyze SAM- dependent arsenite methylation with formation of monomethylarsenite (MMAs) and dimethylarsenite (DMAs). In addition, in vitro analyses confirmed the unique interaction between TtArsM and TtSmtB. Next, a highly efficient ThermoCas9- based genome-editing tool was developed to delete the TtArsM-encoding gene on the T. thermophilus genome and to confirm its involvement in the arsenite detoxification system. Finally, the TtarsX efflux pump gene in the T. thermophilus ΔTtarsM genome was substituted by a gene encoding a stabilized yellow fluorescent protein (sYFP) to create a sensitive genome-based bioreporter system for the detection of arsenic ions.ImportanceWe here describe the discovery of an unknown protein by using a proteomic approach with a functionally related protein as bait. Remarkably, we successfully obtained a novel type of enzyme through the interaction with a transcription regulator, controlling the expression of this enzyme. Employing this strategy, we isolated TtArsM, the first thermophilic prokaryotic arsenite methyltransferase, as a new enzyme of the arsenic resistance mechanism in T. thermophilus HB27. The atypical arsenite binding site of TtArsM categorizes the enzyme as the first member of a new arsenite methyltransferase type, exclusively present in the Thermus genus. The enzyme methylates arsenite producing MMAs and DMAs. Furthermore, we developed an hyperthermophilic Cas9-based genome-editing tool, active up to 65°C. The tool allowed us to perform highly efficient, marker-free modifications (either gene deletion or insertion) in the T. thermophilus genome. With these modifications, we confirmed the critical role of TtArsM in the arsenite detoxification system and developed a sensitive whole cell bioreporter for arsenic ions. We anticipate that the developed tool can be easily adapted for editing the genomes of other thermophilic bacteria, significantly boosting fundamental and metabolic engineering in hyperthermophilic microorganisms.

Currently, a major technical limitation of microscopy based image analysis is the linkage error – which describes the distance between e.g. the target epitope of cellular protein to the fluorescence emitter, which position is finally detected in a microscope. With continuously improving resolution of today’s (super-resolution) microscopes, the linkage errors can severely hamper the correct interpretation of images and is usually introduced in experiments by the use of standard intracellular staining reagents such as fluorescently labelled antibodies. The linkage error of standard labelled antibodies is caused by the size of the antibody and the random distribution of fluorescent emitters on the antibody surface. Together, these two factors account for a fluorescence displacement of ~40nm when staining proteins by indirect immunofluorescence; and ~20nm when staining with fluorescently coupled primary antibodies. In this study, we describe a class of staining reagents that effectively reduce the linkage error by more than five-fold when compared to conventional staining techniques. These reagents, called Fluo-N-Fabs, consist of an antigen binding fragment of a full-length antibody (Fab / fragment antigen binding) that is selectively conjugated at the N-terminal amino group with fluorescent organic molecules, thereby reducing the distance between the fluorescent emitter and the protein target of the analysis. Fluo-N-Fabs also exhibit the capability to penetrate tissues and highly crowded cell compartments, thus allowing for the efficient detection of cellular epitopes of interest in a wide range of fixed samples. We believe this class of reagents realize an unmet need in cell biological super resolution imaging studies where the precise localization of the target of interest is crucial for the understanding of complex biological phenomena.

Objectives Artifactually altered glycated hemoglobin (HbA1c) concentrations are frequently linked to hemoglobin (Hb) variants. Their expression and detection require in-depth analysis. Methods Cation exchange high performance liquid chromatography (HPLC) (Bio-Rad Variant™ II; Trinity Biotech Premier Hb9210 Resolution), capillary electrophoresis (CE) (Sebia Capillarys 2 Flex Piercing) and mass spectrometry (MS) (Waters) were used for variant detection; Sanger sequencing, multiplex ligation-dependent probe amplification (MLPA) and next generation sequencing (NGS) were used for DNA analysis; HbA1c was measured with cation exchange HPLC (Bio-Rad Variant™ II; Arkray Adams HA-8180V; Tosoh HLC-723 G7), CE (Sebia Capillarys 2 Flex Piercing), boronate affinity HPLC (Trinity Biotech Hb9210 Premier), immunoassay (Cobas c501 Tina-quant HbA1c Gen. 3; Nihon Kohden CHM-4100 Celltac chemi HbA1c HA-411V) and enzymatic assay (Abbott Architect c 8000 HbA1c). Results Hb Yamagata [β132(H10)Lys→Asn; (HBB: c.399A>T)] was identified in the proband by MS after the observation of an abnormal peak in HPLC and CE. A mosaic expression of this variant was detected by NGS (mutant: 8%; wild type: 92%), after negative results in Sanger sequencing. Hb Yamagata interfered with HbA1c measurements by cation exchange HPLC and CE whereas immuno and enzymatic assay values showed good agreement with boronate affinity HPLC measurement. Conclusions A mosaicism of Hb Yamagata was found in a patient with altered HbA1c values. This rare gene variant was detected only by advanced technologies as MS and NGS. The variant interfered with common HbA1c determination methods.

Background: Shp1, a tyrosine-phosphatase-1 containing the Src-homology 2 (SH2) domain, is involved in inflammatory and immune reactions, where it regulates diverse signalling pathways, usually by limiting cell responses through dephosphorylation of target molecules. Moreover, Shp1 regulates actin dynamics. One Shp1 target is Src, which controls many cellular functions including actin dynamics. Src has been previously shown to be activated by a signalling cascade initiated by the cytosolic-phospholipase A2 (cPLA2) metabolite glycerophosphoinositol 4-phosphate (GroPIns4P), which enhances actin polymerisation and motility. While the signalling cascade downstream Src has been fully defined, the mechanism by which GroPIns4P activates Src remains unknown. Methods: Affinity chromatography, mass spectrometry and co-immunoprecipitation studies were employed to identify the GroPIns4P-interactors; among these Shp1 was selected for further analysis. The specific Shp1 residues interacting with GroPIns4P were revealed by NMR and validated by site-directed mutagenesis and biophysical methods such as circular dichroism, isothermal calorimetry, fluorescence spectroscopy, surface plasmon resonance and computational modelling. Morphological and motility assays were performed in NIH3T3 fibroblasts. Results: We find that Shp1 is the direct cellular target of GroPIns4P. GroPIns4P directly binds to the Shp1-SH2 domain region (with the crucial residues being Ser 118, Arg 138 and Ser 140) and thereby promotes the association between Shp1 and Src, and the dephosphorylation of the Src-inhibitory phosphotyrosine in position 530, resulting in Src activation. As a consequence, fibroblast cells exposed to GroPIns4P show significantly enhanced wound healing capability, indicating that GroPIns4P has a stimulatory role to activate fibroblast migration. GroPIns4P is produced by cPLA2 upon stimulation by diverse receptors, including the EGF receptor. Indeed, endogenously-produced GroPIns4P was shown to mediate the EGF-induced cell motility. Conclusions: This study identifies a so-far undescribed mechanism of Shp1/Src modulation that promotes cell motility and that is dependent on the cPLA2 metabolite GroPIns4P. We show that GroPIns4P is required for EGF-induced fibroblast migration and that it is part of a cPLA2/GroPIns4P/Shp1/Src cascade that might have broad implications for studies of immune-inflammatory response and cancer. [Figure not available: see fulltext.]

A PNRS, Lei Federal nº 12.305/2010, estabeleceu um prazo para a extinção das áreas de disposição de resíduos a céu aberto (lixões), o qual foi inicialmente fixado para agosto de 2014. A principal solução para a erradicação destas áreas foi a implantação de aterros sanitários. A dificuldade de realizar a disposição final ambientalmente adequada em aterros sanitários afeta 88% dos municípios brasileiros. A gestão integrada de resíduos, baseada na máxima valorização e redução de rejeitos, tem se mostrado como um caminho alternativo para romper a inércia da gestão inadequada de resíduos sólidos urbanos (RSU) nos municípios brasileiros, e o Estado do Ceará se apresenta como referência para essa concepção. No Estado do Ceará, a política pública para combater o gerenciamento e disposição inadequada de RSU passou por duas tomadas de decisões significativas, com a implementação de: consórcios públicos organizados em função de aterros sanitários regionais (período de 2008 a 2010) e consórcios públicos organizados em função da valorização de RSU (período de 2017 a 2019). O objetivo desta pesquisa foi avaliar como a mudança de estratégia na política pública de gestão de RSU no Estado do Ceará pretende qualificar o gerenciamento de RSU, considerando os avanços e dificuldades enfrentadas. A pesquisa foi desenvolvida a partir de revisão bibliográfica, documental e estudo de caso. Foram visitados 34 municípios cearenses (18%) e acompanhado procedimentos de elaboração dos Planos de Coletas Seletivas Múltiplas (PCSM) pelos consórcios públicos organizados para a valorização de resíduos. O estudo comparativo entre as duas políticas públicas apresentou as diferenças entre as diretrizes e estratégias de implantação. Os Planos de Coletas Seletivas Múltiplas, baseados na valorização de resíduos, propuseram a implantação em três etapas, priorizando a recuperação de resíduos orgânicos. O Governo do Estado do Ceará adequou a forma de repasse dos recursos financeiros oriundos do Imposto sobre Operações relativas à Circulação de Mercadorias e sobre Prestações de Serviços de Transporte Interestadual e Intermunicipal e de Comunicação (ICMS). Esta adequação possibilitou que os consórcios públicos pudessem obter os recursos financeiros necessários para a implantação das instalações previstas nos Planos de Coletas Seletivas Múltiplas em até dois anos. A pesquisa realizou uma avaliação de três consórcios públicos formados na política pública voltada para a valorização dos RSU, sendo dois em seu segundo ano de recebimento dos repasses do ICMS (COMARES-UCV e CPMRS do Sertão de Crateús) e um em seu primeiro ano (CPMRS do Vale do Curu). Os resultados mostram a capacidade dos PCSM na recuperação de RSU, como o PCSM ajudou na estruturação dos consórcios públicos e como a garantia de recursos financeiros para implantação se torna importante para concretizar o planejamento realizado. A dissertação conclui que os PCSM estão adequados para os municípios de pequeno e médio porte e que necessita de readequação futura para os municípios de grande porte no gerenciamento dos resíduos orgânicos. As estratégias definidas nos PCSM apresentam um grande potencial para o rompimento da barreira existente entre o planejamento e a implantação. The PNRS, Federal Law No. 12.305/2010, established a deadline for the extinction of open air waste disposal areas (dumps), which was initially set for August 2014. The main solution for the eradication of these areas was the implementation of sanitary landfills. The difficulty of performing the environmentally adequate final disposal in landfills affects 88% of Brazilian municipalities. Integrated waste management, based on maximum valorization and reduction of waste, has shown itself as an alternative path to break the inertia of inadequate management of urban solid waste (USW) in Brazilian municipalities, and the State of Ceará presents itself as a reference for this conception. In the State of Ceará, the public policy to combat inadequate waste management and disposal has undergone two significant takeaways, with the implementation of: public consortia organized as a function of regional landfills (period from 2008 to 2010) and public consortia organized as a function of waste valorization (period from 2017 to 2019). The objective of this research was to evaluate how the change of strategy in the public policy of solid waste management in the State of Ceará intends to qualify the management of solid waste, considering the advances and difficulties faced. The research was developed from bibliographic and documental review and field work. Thirty-four municipalities from Ceará (18%) were visited and procedures for the elaboration of the Multiple Selective Collection Plans (PCSM) by the public consortiums organized for waste valorization were followed. The comparative study between the two public policies presented the differences between the guidelines and implementation strategies. The Multiple Selective Collection Plans, based on waste valorization, proposed the implantation in three stages, prioritizing the recovery of organic waste. The Government of the State of Ceará adjusted the form of transfer of financial resources from the Tax on Transactions related to the Circulation of Goods and Services on Interstate and Intercity Transport and Communication (ICMS). This adjustment made it possible for the public consortia to obtain the necessary financial resources to implement the facilities foreseen in the Multiple Selective Collection Plans within two years. The research carried out an evaluation of three public consortiums formed in the public policy aimed at the valorization of solid waste, two in their second year of receiving ICMS transfers (COMARES-UCV and CPMRS of Sertão de Crateús) and one in its first year (CPMRS of Vale do Curu). The results show the capacity of the PCSM in the recovery of MSW, how the PCSM helped in the structuring of the public consortia, and how the guarantee of financial resources for implementation becomes important to concretize the planning carried out. The dissertation concludes that the PCSM are adequate for small and medium-sized municipalities and that it needs future readjustment for large-sized municipalities in the management of organic waste. The strategies defined in the PCSM present a great potential for breaking the barrier between planning and implementation.

The tumor microenvironment modulates cancer growth. Extracellular vesicles (EVs) have been identified as key mediators of intercellular communication, but their role in tumor growth is largely unexplored. Here, we demonstrate that EVs from sarcoma patients promote neoangiogenesis via a purinergic X receptor 4 (P2XR4) -dependent mechanism in vitro and in vivo. Using a proteomic approach, we analyzed the protein content of plasma EVs and identified critical activated pathways in human umbilical vein endothelial cells (HUVECs) and human progenitor hematopoietic cells (CD34+). We then showed that vessel formation was due to rapid mitochondrial activation, intracellular Ca2+ mobilization, increased extracellular ATP, and trafficking of the lysosomal P2XR4 to the cell membrane, which is required for cell motility and formation of stable branching vascular networks. Cell membrane translocation of P2XR4 was induced by proteins and chemokines contained in EVs (e.g. Del-1 and SDF-1). Del-1 was found expressed in many EVs from sarcoma tumors and several tumor types. P2XR4 blockade reduced EVs-induced vessels in angioreactors, as well as intratumor vascularization in mouse xenografts. Together, these findings identify P2XR4 as a key mediator of EVs-induced tumor angiogenesis via a signaling mediated by mitochondria-lysosome-sensing response in endothelial cells, and indicate a novel target for therapeutic interventions.

Artifactually altered glycated hemoglobin (HbACation exchange high performance liquid chromatography (HPLC) (Bio-Rad Variant™ II; Trinity Biotech Premier Hb9210 Resolution), capillary electrophoresis (CE) (Sebia Capillarys 2 Flex Piercing) and mass spectrometry (MS) (Waters) were used for variant detection; Sanger sequencing, multiplex ligation-dependent probe amplification (MLPA) and next generation sequencing (NGS) were used for DNA analysis; HbAHb Yamagata [β132(H10)Lys→Asn; (A mosaicism of Hb Yamagata was found in a patient with altered HbA

Plants, including cocoa bean, are the main source of metabolites with multiple biological functions. Polyphenol extracts are widely used as a nutraceutical supplement for their well-known health-promoting role. In this paper, a preliminary untargeted metabolic screening was carried out by matrix-assisted laser desorption/ionization (MALDI)-time of flight (TOF)/TOF on a pool of chocolate samples made by cocoa beans of different geographical areas. Then, a targeted approach was developed for polyphenol quantification by an optimized Liquid chromatography (LC)-tandem mass spectrometry (MS/MS) method multiple reaction monitoring (MRM) ion mode. Detection limit of polyphenol standard ranged between 1 and 25 pg/μl with variation coefficient lower than 15%. External calibration curves were used for quantification of polyphenols in 18 samples. Fifty polyphenols were detected in a single LC-MRM/MS run and quantified by monitoring almost 90 transitions in a 5-minute run. The polyphenols content of different cocoa beans from several countries was finally compared by principal component analysis (PCA) statistical analysis suggesting that the chocolate made by Ecuador cocoa beans showed the highest level of polyphenols.

8-Oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) is one of the major DNA modifications and a potent pre-mutagenic lesion prone to mispair with 2′-deoxyadenosine (dA). Several thousand residues of 8-oxodG are constitutively generated in the genome of mammalian cells, but their genomic distribution has not yet been fully characterized. Here, by using OxiDIP-Seq, a highly sensitive methodology that uses immuno-precipitation with efficient anti–8-oxodG antibodies combined with high-throughput sequencing, we report the genome-wide distribution of 8-oxodG in human non-tumorigenic epithelial breast cells (MCF10A), and mouse embryonic fibroblasts (MEFs). OxiDIP-Seq revealed sites of 8-oxodG accumulation overlapping with γH2AX ChIP-Seq signals within the gene body of transcribed long genes, particularly at the DNA replication origins contained therein. We propose that the presence of persistent single-stranded DNA, as a consequence of transcription-replication clashes at these sites, determines local vulnerability to DNA oxidation and/or its slow repair. This oxidatively-generated damage, likely in combination with other kinds of lesion, might contribute to the formation of DNA double strand breaks and activation of DNA damage response.

Background information Up-regulated Gene clone 7 (URG7) is an ER resident protein, whose expression is up-regulated in the presence of hepatitis B virus X antigen (HBxAg) during HBV infection. In virus-infected hepatocytes, URG7 shows an anti-apoptotic activity due to the PI3K/AKT signalling activation, does not seem to have tumorigenic properties, but it appears to promote the development and progression of fibrosis. However, the molecular mechanisms underlying URG7 activity remain largely unknown. Results To shed light on URG7 activity, we first analysed its interactome in HepG2 transfected cells: this analysis suggests that URG7 could have a role in affecting protein synthesis, folding and promoting proteins degradation. Moreover, keeping into account its subcellular localisation in the ER and that several viral infections give rise to ER stress, a panel of experiments was performed to evaluate a putative role of URG7 in ER stress. Our main results demonstrate that in ER-stressed cells URG7 is able to modulate the expression of Unfolded Protein Response (UPR) markers towards survival outcomes, up-regulating GRP78 protein and down-regulating the pro-apoptotic protein CHOP. Furthermore, URG7 reduces the ER stress by decreasing the amount of unfolded proteins, by increasing both the total protein ubiquitination and the AKT activation and reducing Caspase 3 activation. Conclusions All together these data suggest that URG7 plays a pivotal role as a reliever of ER stress-induced apoptosis. Significance This is the first characterisation of URG7 activity under ER stress conditions. The results presented here will help to hypothesise new strategies to counteract the antiapoptotic activity of URG7 in the context of the viral infection.

STAT1 and STAT3 are two transcription factors involved in a lot of cellular functions such as immune response, proliferation, apoptosis, and cell survival. A number of literature evidences described a yin-yang relationship between activation of STAT1 and STAT3 in neurodegenerative disorders where STAT1 exerts a pro-apoptotic effect whereas STAT3 shows neuroprotective properties through the inhibition of apoptosis. Although the role of oxidative-stress in the pathogenesis of neurodegeneration is clearly described, its influence in the regulation of these pathways is poorly understood. Herein, we demonstrate that H2O2 rapidly induces phosphorylation of STAT1 whereas it is not able to influence phosphorylation of STAT3 in mouse microglia BV2 cells. The analysis of the molecular mechanism of STATs signaling reveals that H2O2 induces S-glutathionylation of both STAT1 and STAT3. The same post-translational event exerts an opposing role in the regulation of STAT1 and STAT3 signaling. These data not only confirm redox sensibility of STAT3 signaling but also reveal for the first time that STAT1 is susceptible to redox regulation. A deep study of the molecular mechanism of STAT1 redox regulation, identifies Cys324 and Cys492 as the main targets of S-glutathionylation and confirms that S-glutathionylation does not impair JAK2 mediated STAT1 tyrosine phosphorylation. These results demonstrate that both phosphorylation and glutathionylation contribute to activation of STAT1 during oxidative stress and underline that the same post-translation event exerts an opposing role in the regulation of STAT1 and STAT3 signaling in microglia cells. © 2018

Cerebral tissues in human remains are rare archaeological discoveries. These tissues are typically saponified, meaning that their triglycerides have been converted to glycerol and fatty acid salts, or soap. In c.e. 79, a volcanic hot ash avalanche rapidly killed the inhabitants of Pompeii and Herculaneum. In the 1960s, at the Collegium Augustalium in Herculaneum, a human victim of the avalanche was found lying on a wooden bed, buried by volcanic ash. In this victim’s skull, we discovered apparent brain remains that were vitrified instead of saponified.

Many details of oxidative folding of proteins remain obscure, in particular, the role of oxidized glutathione (GSSG). This study reveals some unknown aspects. When a reduced ribonuclease A refolds in the presence of GSSG, most of its eight cysteines accomplish a very fast glutathionylation. In particular, one single cysteine, identified as Cys95 by mass spectrometry, displays 3600 times higher reactivity when compared with an unperturbed protein cysteine. Furthermore, the other five cysteines show 40&ndash, 50 times higher reactivity toward GSSG. This phenomenon is partially due to a low pKa value of most of these cysteines (average pKa = 7.9), but the occurrence of a reversible GSSG-ribonuclease complex (KD = 0.12 mM) is reasonably responsible for the extraordinary hyper-reactivity of Cys95. Neither hyper-reactivity nor some protein-disulfide complexes have been found by reacting a reduced ribonuclease with other natural disulfides i.e., cystine, cystamine, and homocystine. Hyper-reactivity of all cysteines was observed toward 5,5&rsquo, dithiobis-(2-nitrobenzoic acid). Given that GSSG is present in high concentrations in the endoplasmic reticulum, this property may shed light on the early step of its oxidative folding. The ultra-rapid glutathionylation of cysteines, only devoted to form disulfides, is a novel property of the molten globule status of the ribonuclease.

The TRAnsport Protein Particle (TRAPP) complex controls multiple steps along the secretory, endocytic and autophagic pathways and is thus strategically positioned to mediate the adaptation of membrane trafficking to diverse environmental conditions including acute stress. We identified TRAPP as a key component of a branch of the integrated stress response that impinges on the secretory pathway. We found that TRAPP associates with, and drives the recruitment of the inner components of the COPII coat to, SGs. The sequestration to SGs of COPII, required for the ER export of newly synthesized proteins, and of TRAPP, the exchange factor for Rab1, a GTPase controlling the architecture of the Golgi complex, leads to arrest of the secretory activity and to the disorganization of the Golgi complex. Interestingly, the relocation of TRAPP and COPII to SGs only occurs in actively proliferating cells and it does it in a CDK1/2 dependent manner. We show that CDK1/2 activity controls the membrane-cytosol cycle of COPII at ER exit sites (ERES) and that CDK1/2 inhibition/depletion prevents the relocation of COPII and TRAPP to SGs by stabilizing them at the ERES. Importantly, TRAPP is not just a passive constituent of SGs but controls their maturation. This includes the acquisition of signaling components, such as RACK1 and Raptor, whose sequestration to SGs is needed to mediate the pro-survival response. SGs that assemble in TRAPP-depleted cells are no longer able to sequester RACK1 and Raptor thus rendering the cells more prone to undergo apoptosis upon stress exposure. Altogether, our findings reveal a new property of the integrated stress response that is acquired through the recruitment of TRAPP to SGs: a high grade of plasticity that tailors the secretory pathway to stress according to different cell growth states.

Hb variants are structurally abnormal haemoglobins which can originate a wide range of phenotypes from clinically silent conditions to very severe disorders. In many cases, diagnosis is very difficult due to the instability of Hb mutants or the occurrence of misleading symptoms, such as cyanosis or hypoxia. Here we report the case of a young female with undiagnosed chronic haemolytic anaemia and low oxygen saturation in the absence of respiratory distress. High performance liquid chromatography showed the occurrence of an abnormal peak in the HbA2 region, which disappeared few days after blood sampling. Genetic analysis of both α genes revealed the -α3.7 deletion in heterozygous state and a novel mutation c.130 T C leading to the substitution of Phenylalanine at codon 43 with Leucine in the α1 gene. This substitution originated a new Hb variant, named Hb Vanvitelli, with a molecular mass of 15,092.2 ± 0.4 Da. Biochemical and laboratory tests described a hyper unstable Hb variant with altered oxygen affinity that was clinically significant only when co-inherited with genetic defects affecting the α2 locus. This case highlights the genetic complexity and diagnostic pitfalls of Hb variants, defined "experiments of nature" which can generate severe clinical conditions.

In the context of the vascular effects of hydrogen sulfide (H

Asparaginyl deamidation, a spontaneous protein post-biosynthetic modification, determines isoaspartyl formation and structure-function impairment. The isoaspartyl protein carboxyl-O-methyltransferase (PCMT1; EC 2.1.1.77) catalyzes the repair of the isopeptide bonds at isoaspartyl sites, preventing deamidation-related functional impairment. Protein deamidation affects key apoptosis mediators, such as BclxL, thus increasing susceptibility to apoptosis, whereas PCMT1 activity may effectively counteract such alterations. The aim of this work was to establish the role of RNAi as a potential mechanism for regulating PCMT1 expression and its possible implications in apoptosis. We investigated the regulatory properties of the microRNA 15a/16-1 cluster on PCMT1 expression on HepG2 cells. MicroRNA 15a or microRNA 16-1 transfection, as well as their relevant antagonists, showed that PCMT1 is effectively regulated by this microRNA cluster. The direct interaction of these two microRNAs with the seed sequence at the 3' UTR of PCMT1 transcripts was demonstrated by the luciferase assay system. The role of PCMT1 down-regulation in conditioning the susceptibility to apoptosis was investigated using various specific siRNA or shRNA approaches, to prevent non-PCMT1-specific pleiotropic effects to take place. We found that PCMT1 silencing is associated with an increase of the BclxL isoform reported to be inactivated by deamidation, thus making cells more susceptible to apoptosis induced by cisplatinum. We conclude that PCMT1 is effectively regulated by the microRNA 15a/16-1 cluster and is involved in apoptosis by preserving the structural stability and biological function of BclxL from deamidation. Control of PCMT1 expression by microRNA 15a/16-1 may thus represent a late checkpoint in apoptosis regulation.

The isoforms of lycopene, carotenoids, and their derivatives including precursors of vitamin A are compounds relevant for preventing chronic degenerative diseases such as cardiovascular diseases and cancer. Tomatoes are a major source of these compounds. However, cooking and successive metabolic processes determine the bioavailability of tomatoes in human nutrition. To evaluate the effect of acute/chronic cooking procedures on the bioavailability of lycopene and carotene isoforms in human plasma, we measured the blood levels of these compounds and of the serum antioxidant potential in volunteers after a meal containing two different types of tomato sauce (rustic or strained). Using a randomized cross-over administration design, healthy volunteers were studied, and the above indicated compounds were determined by HPLC. The results indicate an increased bioavailability of the estimated compounds and of the serum antioxidant potential with both types of tomato purée and the subsequently derived sauces (the increase was greater with strained purée). This study sheds light on the content of nutrient precursors of vitamin A and other antioxidant compounds derived from tomatoes cooked with different strategies. Lastly, our study indicates that strained purée should be preferred over rustic purée.

The human flavoenzyme D-amino acid oxidase (hDAAO) degrades the NMDA-receptor modulator D-serine in the brain. Whereas hDAAO has been extensively characterized, little is known about its main modulator pLG72, a small protein encoded by the primate-specific gene G72 that has been associated with schizophrenia susceptibility. pLG72 interacts with neosynthesized hDAAO, promoting its inactivation and degradation. In this work we used low-resolution techniques to characterize the surface topology of the hDAAO-pLG72 complex. By using limited proteolysis coupled to mass spectrometry we could map the exposed regions in the two proteins after complex formation and highlighted an increased sensitivity to proteolysis of hDAAO in complex with pLG72. Cross-linking experiments by using bis(sulfosuccinimidyl)suberate identified the single covalent bond between T182 in hDAAO and K62 in pLG72. In order to validate the designed mode of interaction, three pLG72 variants incrementally truncated at the C-terminus, in addition to a form lacking the 71 N-terminal residues, were produced. All variants were dimeric, folded, and interacted with hDAAO. The strongest decrease in affinity for hDAAO (as well as for the hydrophobic drug chlorpromazine) was apparent for the N-terminally deleted pLG7272-153 form, which lacked K62. On the other hand, eliminating the disordered C-terminal tail yielded a more stable pLG72 protein, improved the binding to hDAAO, although giving lower enzyme inhibition. Elucidation of the mode of hDAAO-pLG72 interaction now makes it possible to design novel molecules that, by targeting the protein complex, can be therapeutically advantageous for diseases related to impairment in D-serine metabolism. This article is protected by copyright. All rights reserved.

In the context of the vascular effects of hydrogen sulfide (H2S), it is known that this gaseous endogenous biological modulator of inflammation, oxidative stress, etc. is a potent vasodilator. Chronic renal failure, a common disease affecting the aging population, is characterized by low levels of H2S in plasma and tissues, which could mediate their typical hypertensive pattern, along with other abnormalities. Lanthionine and homolanthionine, natural non-proteinogenic amino acids, are formed as side products of H2S production. Also in consideration of the intrinsic difficulties in H2S measuring, these compounds have been proposed as reliable and stable markers of H2S synthesis. However, in the setting of chronic renal failure patients on hemodialysis, they represent typical retention products (without ruling out the possibility of an increased intestinal synthesis) and prospective novel uremic toxins. Here, a method utilizing liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) in multiple reaction monitoring ion mode has been developed and evaluated for the determination of these key H2S metabolites in plasma, by using a triple quadrupole mass spectrometer.

Hb variants are structurally abnormal haemoglobins which can originate a wide range of phenotypes from clinically silent conditions to very severe disorders. In many cases, diagnosis is very difficult due to the instability of Hb mutants or the occurrence of misleading symptoms, such as cyanosis or hypoxia. Here we report the case of a young female with undiagnosed chronic haemolytic anaemia and low oxygen saturation in the absence of respiratory distress. High performance liquid chromatography showed the occurrence of an abnormal peak in the HbA2 region, which disappeared few days after blood sampling. Genetic analysis of both α genes revealed the −α3.7 deletion in heterozygous state and a novel mutation c.130 T > C leading to the substitution of Phenylalanine at codon 43 with Leucine in the α1 gene. This substitution originated a new Hb variant, named Hb Vanvitelli, with a molecular mass of 15,092.2 ± 0.4 Da. Biochemical and laboratory tests described a hyper unstable Hb variant with altered oxygen affinity that was clinically significant only when co-inherited with genetic defects affecting the α2 locus. This case highlights the genetic complexity and diagnostic pitfalls of Hb variants, defined “experiments of nature” which can generate severe clinical conditions.

Identification of proteins in paintings and polychrome objects is a challenge, which requires the development of tailored analytical approaches. In the present study, a targeted proteomics approach was developed for discriminating among the three most common proteinaceous materials used as paint binders, i.e. milk, egg, and animal glue. In this study a specific database of peptides was created based on tandem MS analyses of tryptic digests of several paint samples collected from a variety of art objects of different ages and conservation conditions. Specific peptide markers of each protein were then selected and monitored by LC-MSMS in Multiple Reaction Monitoring (MRM) ion mode, together with their specific precursor ion-product ion transitions, as defined by their unique amino acid sequence. The developed method enabled a sensitive and reliable detection of the target peptides in a selection of case studies, leading to the unambiguous identification of the proteins used as paint binders. The method showed greatly increased sensitivity compared to currently available strategies.