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1.
EMBO J ; 42(8): e110454, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-36727601

RESUMO

Cells need to sense stresses to initiate the execution of the dormant cell death program. Since the discovery of the first BH3-only protein Bad, BH3-only proteins have been recognized as indispensable stress sensors that induce apoptosis. BH3-only proteins have so far not been identified in Drosophila despite their importance in other organisms. Here, we identify the first Drosophila BH3-only protein and name it sayonara. Sayonara induces apoptosis in a BH3 motif-dependent manner and interacts genetically and biochemically with the BCL-2 homologous proteins, Buffy and Debcl. There is a positive feedback loop between Sayonara-mediated caspase activation and autophagy. The BH3 motif of sayonara phylogenetically appeared at the time of the ancestral gene duplication that led to the formation of Buffy and Debcl in the dipteran lineage. To our knowledge, this is the first identification of a bona fide BH3-only protein in Drosophila, thus providing a unique example of how cell death mechanisms can evolve both through time and across taxa.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/genética , Apoptose/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas de Drosophila/metabolismo
2.
Brief Bioinform ; 22(2): 642-663, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33147627

RESUMO

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is a novel virus of the family Coronaviridae. The virus causes the infectious disease COVID-19. The biology of coronaviruses has been studied for many years. However, bioinformatics tools designed explicitly for SARS-CoV-2 have only recently been developed as a rapid reaction to the need for fast detection, understanding and treatment of COVID-19. To control the ongoing COVID-19 pandemic, it is of utmost importance to get insight into the evolution and pathogenesis of the virus. In this review, we cover bioinformatics workflows and tools for the routine detection of SARS-CoV-2 infection, the reliable analysis of sequencing data, the tracking of the COVID-19 pandemic and evaluation of containment measures, the study of coronavirus evolution, the discovery of potential drug targets and development of therapeutic strategies. For each tool, we briefly describe its use case and how it advances research specifically for SARS-CoV-2. All tools are free to use and available online, either through web applications or public code repositories. Contact:evbc@unj-jena.de.


Assuntos
COVID-19/prevenção & controle , Biologia Computacional , SARS-CoV-2/isolamento & purificação , Pesquisa Biomédica , COVID-19/epidemiologia , COVID-19/virologia , Genoma Viral , Humanos , Pandemias , SARS-CoV-2/genética
3.
Sante Publique ; 35(HS1): 173-177, 2023 12 01.
Artigo em Francês | MEDLINE | ID: mdl-38040642

RESUMO

As it seems likely that France, at the forefront in the use of surgical robotic platforms, will authorize the deployment of dental robots in the short term, the purpose of this article is to question what is at stake in this technological revolution, for dental professionals, regulators but also (and above all) for patients: what awareness-raising will the intervention of machines bring? How does robotics reshuffle the cards of the care relationship? What are the ethical and public health issues? After having defined dental robots as non-humanoid, automated surgical devices with exclusive restorative vocation, we will see how the field of dental robotics currently oscillates between hopes and illusions. We will describe the new responsibilities and ethical requirements related to the introduction of these AI-powered technical objects, as well as the necessary safeguards that have to be implemented in order to avoid any moral buffer and to protect patients from any robotization (literally or metaphorically in the sense of 'zombification'). Finally, we will show that ultimately the question of robot-dentists is the natural evolution of unreasonable application of industrial processes to the rationalization of health and ectopic, neo-liberal practices shifting healthcare into a commercial commodity. Patients can participate in reversing this trend, by recalling that the centrality of the human person is the cornerstone of health professions.


Comme il est vraisemblable que la France, à la pointe dans l'utilisation des plateformes robotiques chirugicales, autorise à court terme le déploiement de robots-dentistes sur son territoire, l'objectif de cet article est d'interroger ce qui se joue dans cette révolution technologique, pour les professionnels du dentaire, les régulateurs, mais aussi (et surtout) pour les patients : quelle(s) prise(s) de conscience l'intervention de la machine et les mutations qui lui sont associées peuvent-elles amener ? Comment la robotique rebat-elle les cartes de la relation de soin ? Pour quels enjeux éthiques et de santé publique ? Après avoir défini les robots-dentistes comme des dispositifs chirurgicaux automatisés à vocation réparatrice, pour l'instant non anthropomorphes, nous verrons comment le domaine de la robotique dentaire oscille entre espoirs et illusions. Nous décrirons les nouvelles responsabilités et exigences éthiques liées à l'introduction de ces objets techniques équipés d'intelligence artificielle, ainsi que les nécessaires garde-fous à implémenter pour éviter toute distanciation morale et pour protéger la patientèle de toute robotisation (au sens propre ou au sens métaphorique de « zombification ¼). Nous montrerons enfin que la question du robot-dentiste n'est finalement que l'évolution naturelle de l'application déraisonnée de procédés industriels à la rationalisation de la santé et de pratiques néolibérales ectopiques conduisant à sa marchandisation. Les patients peuvent participer à l'infléchissement de cette tendance, en rappelant que la centralité de la personne humaine constitue la pierre angulaire des métiers de la santé.


Assuntos
Procedimentos Cirúrgicos Bucais , Robótica , Humanos , Odontólogos , França , Implantação Dentária , Inteligência Artificial , Procedimentos Cirúrgicos Bucais/tendências
4.
PLoS Genet ; 14(8): e1007592, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30142151

RESUMO

Yeast WHI2 was originally identified in a genetic screen for regulators of cell cycle arrest and later suggested to function in general stress responses. However, the function of Whi2 is unknown. Whi2 has predicted structure and sequence similarity to human KCTD family proteins, which have been implicated in several cancers and are causally associated with neurological disorders but are largely uncharacterized. The identification of conserved functions between these yeast and human proteins may provide insight into disease mechanisms. We report that yeast WHI2 is a new negative regulator of TORC1 required to suppress TORC1 activity and cell growth specifically in response to low amino acids. In contrast to current opinion, WHI2 is dispensable for TORC1 inhibition in low glucose. The only widely conserved mechanism that actively suppresses both yeast and mammalian TORC1 specifically in response to low amino acids is the conserved SEACIT/GATOR1 complex that inactivates the TORC1-activating RAG-like GTPases. Unexpectedly, Whi2 acts independently and simultaneously with these established GATOR1-like Npr2-Npr3-Iml1 and RAG-like Gtr1-Gtr2 complexes, and also acts independently of the PKA pathway. Instead, Whi2 inhibits TORC1 activity through its binding partners, protein phosphatases Psr1 and Psr2, which were previously thought to only regulate amino acid levels downstream of TORC1. Furthermore, the ability to suppress TORC1 is conserved in the SKP1/BTB/POZ domain-containing, Whi2-like human protein KCTD11 but not other KCTD family members tested.


Assuntos
Aminoácidos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Animais , Células COS , Chlorocebus aethiops , Regulação da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Monoméricas de Ligação ao GTP/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética
5.
Trends Biochem Sci ; 40(12): 736-748, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26541461

RESUMO

B cell lymphoma-2 (BCL-2)-related proteins control programmed cell death through a complex network of protein-protein interactions mediated by BCL-2 homology 3 (BH3) domains. Given their roles as dynamic linchpins, the discovery of novel BH3-containing proteins has attracted considerable attention. However, without a clearly defined BH3 signature sequence the BCL-2 family has expanded to include a nebulous group of nonhomologous BH3-only proteins, now justified by an intriguing twist. We present evidence that BH3s from both ordered and disordered proteins represent a new class of short linear motifs (SLiMs) or molecular recognition features (MoRFs) and are diverse in their evolutionary histories. The implied corollaries are that BH3s have a broad phylogenetic distribution and could potentially bind to non-BCL-2-like structural domains with distinct functions.


Assuntos
Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/química , Motivos de Aminoácidos , Animais , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Humanos , Modelos Moleculares , Conformação Proteica
6.
Ann Neurol ; 84(5): 766-780, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30295347

RESUMO

OBJECTIVE: Several small case series identified KCTD7 mutations in patients with a rare autosomal recessive disorder designated progressive myoclonic epilepsy (EPM3) and neuronal ceroid lipofuscinosis (CLN14). Despite the name KCTD (potassium channel tetramerization domain), KCTD protein family members lack predicted channel domains. We sought to translate insight gained from yeast studies to uncover disease mechanisms associated with deficiencies in KCTD7 of unknown function. METHODS: Novel KCTD7 variants in new and published patients were assessed for disease causality using genetic analyses, cell-based functional assays of patient fibroblasts and knockout yeast, and electron microscopy of patient samples. RESULTS: Patients with KCTD7 mutations can exhibit movement disorders or developmental regression before seizure onset, and are distinguished from similar disorders by an earlier age of onset. Although most published KCTD7 patient variants were excluded from a genome sequence database of normal human variations, most newly identified patient variants are present in this database, potentially challenging disease causality. However, genetic analysis and impaired biochemical interactions with cullin 3 support a causal role for patient KCTD7 variants, suggesting deleterious alleles of KCTD7 and other rare disease variants may be underestimated. Both patient-derived fibroblasts and yeast lacking Whi2 with sequence similarity to KCTD7 have impaired autophagy consistent with brain pathology. INTERPRETATION: Biallelic KCTD7 mutations define a neurodegenerative disorder with lipofuscin and lipid droplet accumulation but without defining features of neuronal ceroid lipofuscinosis or lysosomal storage disorders. KCTD7 deficiency appears to cause an underlying autophagy-lysosome defect conserved in yeast, thereby assigning a biological role for KCTD7. Ann Neurol 2018;84:774-788.


Assuntos
Autofagia/genética , Lisossomos/genética , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Canais de Potássio/deficiência , Idade de Início , Pré-Escolar , Feminino , Humanos , Lactente , Lisossomos/patologia , Masculino , Mutação , Linhagem , Canais de Potássio/genética , Proteínas de Saccharomyces cerevisiae/genética
7.
Mol Ther ; 25(2): 534-546, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28153100

RESUMO

Melanoma is a highly metastatic and deadly form of cancer. Invasive melanoma cells overexpress integrin αvß3, which is a well-known target for Arg-Gly-Asp-based (RGD) peptides. We developed a sophisticated method to synthetize milligram amounts of a targeted vector that allows the RGD-mediated targeting, internalization, and release of a mitochondria-disruptive peptide derived from the pro-apoptotic Bax protein. We found that 2.5 µM Bax[109-127] was sufficient to destabilize the mitochondria in ten different tumor cell lines, even in the presence of the anti-apoptotic Bcl2 protein, which is often involved in tumor resistance. This pore-forming peptide displayed antitumor activity when it was covalently linked by a disulfide bridge to the tetrameric RAFT-c[RGD]4-platform and after intravenous injection in a human melanoma tumor model established in humanized immuno-competent mice. In addition to its direct toxic effect, treatment with this combination induced the release of the immuno-stimulating factor monocyte chimoattractant protein 1 (MCP1) in the blood and a decrease in the level of the pro-angiogenic factor FGF2. Our novel multifunctional, apoptosis-inducing agent could be further customized and assayed for potential use in tumor-targeted therapy.


Assuntos
Melanoma/metabolismo , Melanoma/patologia , Fragmentos de Peptídeos/farmacologia , Proteína X Associada a bcl-2/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Melanoma/tratamento farmacológico , Camundongos , Camundongos Knockout , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/síntese química , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
PLoS One ; 19(3): e0301372, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38547143

RESUMO

The importance of mitochondria in tissue homeostasis, stress responses and human diseases, combined to their ability to transition between various structural and functional states, makes them excellent organelles for monitoring cell health. There is therefore a need for technologies to accurately analyze and quantify changes in mitochondrial organization in a variety of cells and cellular contexts. Here we present an innovative computerized method that enables accurate, multiscale, fast and cost-effective analysis of mitochondrial shape and network architecture from confocal fluorescence images by providing more than thirty features. In order to facilitate interpretation of the quantitative results, we introduced two innovations: the use of Kiviat-graphs (herein named MitoSpider plots) to present highly multidimensional data and visualization of the various mito-cellular configurations in the form of morphospace diagrams (called MitoSigils). We tested our fully automated image analysis tool on rich datasets gathered from live normal human skin cells cultured under basal conditions or exposed to specific stress including UVB irradiation and pesticide exposure. We demonstrated the ability of our proprietary software (named MitoTouch) to sensitively discriminate between control and stressed dermal fibroblasts, and between normal fibroblasts and other cell types (including cancer tissue-derived fibroblasts and primary keratinocytes), showing that our automated analysis captures subtle differences in morphology. Based on this novel algorithm, we report the identification of a protective natural ingredient that mitigates the deleterious impact of hydrogen peroxide (H2O2) on mitochondrial organization. Hence we conceived a novel wet-plus-dry pipeline combining cell cultures, quantitative imaging and semiotic analysis for exhaustive analysis of mitochondrial morphology in living adherent cells. Our tool has potential for broader applications in other research areas such as cell biology and medicine, high-throughput drug screening as well as predictive and environmental toxicology.


Assuntos
Peróxido de Hidrogênio , Mitocôndrias , Humanos , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo , Mitocôndrias/metabolismo , Software , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
9.
J Cell Sci ; 124(Pt 4): 556-64, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21245196

RESUMO

Although many cancer cells are primed for apoptosis, they usually develop resistance to cell death at several levels. Permeabilization of the outer mitochondrial membrane, which is mediated by proapoptotic Bcl-2 family members such as Bax, is considered as a point of no return for initiating apoptotic cell death. This crucial role has placed Bcl-2 family proteins as recurrent targets for anticancer drug development. Here, we propose and demonstrate a new concept based on minimal active versions of Bax to induce cell death independently of endogenous Bcl-2 proteins. We show that membrane-active segments of Bax can directly induce the release of mitochondria-residing apoptogenic factors and commit tumor cells promptly and irreversibly to caspase-dependent apoptosis. On this basis, we designed a peptide encompassing part of the Bax pore-forming domain, which can target mitochondria, induce cytochrome c release and trigger caspase-dependent apoptosis. Moreover, this Bax-derived 'poropeptide' produced effective tumor regression after peritumoral injection in a nude mouse xenograft model. Thus, peptides derived from proteins that form pores in the mitochondrial outer membrane represent novel templates for anticancer agents.


Assuntos
Antineoplásicos/metabolismo , Apoptose , Neoplasias/fisiopatologia , Peptídeos/metabolismo , Proteína X Associada a bcl-2/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Citocromos c/metabolismo , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias/tratamento farmacológico , Peptídeos/química , Peptídeos/genética , Peptídeos/farmacologia , Estrutura Terciária de Proteína , Proteína X Associada a bcl-2/química , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/farmacologia
10.
Hum Reprod ; 28(3): 729-39, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23293224

RESUMO

STUDY QUESTION: What is the expression status and subcellular localization of the maternally expressed Bcl-2 family member, BCL2L10, in early human embryos of diverse developmental stages and quality? SUMMARY ANSWER: The anti-apoptotic protein, BCL2L10, is expressed in human preimplantation embryos at least until the blastocyst stage and appears to be differentially distributed at the subcellular level between viable embryos and fragmented or arrested embryos. WHAT IS KNOWN ALREADY: BCL2L10 is an anti-apoptotic member of the BCL-2 family that shows abundant expression in human oocytes and limited sequence conservation to its mouse homologue. STUDY DESIGN, SIZE, DURATION: Embryos donated with informed consent by couples consulting for infertility in the Department of Reproductive Medicine (Hôpital Femme Mère Enfant, Bron, France) were divided into two groups: high quality embryos (n = 18) and poor quality embryos (n = 30). Semen samples (n = 4) were obtained after informed consent from men consulting for couple infertility. Experiments involving human preimplantation embryos were performed between January and December 2009. PARTICIPANTS/MATERIALS, SETTING, METHODS: We examined BCL2L10 expression and subcellular localization in early human embryos by using immunofluorescence and confocal microscopy. The subcellular distribution of BCL2L10 was also studied in ejaculated sperm cells and in isolated mouse skeletal muscle fibres. MAIN RESULTS AND THE ROLE OF CHANCE: The BCL2L10 protein was detectable in healthy human preimplantation embryos at least until the blastocyst stage. In high-quality embryos, BCL2L10 was predominantly cytoplasmic with mitochondrial localization. In contrast, BCL2L10 exhibited extra-mitochondrial localization in abnormal embryos, and was nuclear-cytoplasmic in approximately half (17/30) of the poor-quality embryos. Morphologically fragmented embryos showed coexistence of blastomeres with BCL2L10-positive expression and blastomeres or fragments negative for BCL2L10. LIMITATIONS, REASONS FOR CAUTION: Future studies are needed to evaluate whether embryo quality is related to an exclusive mitochondrial localization of BCL2L10. Mechanisms mediating the nuclear translocation of BCL2L10 in abnormal embryos and functions of this nuclear pool of BCL2L10 are currently unknown. WIDER IMPLICATIONS OF THE FINDINGS: The nuclear localization of BCL2L10 in abnormal embryos suggests a potential role for this protein in pathological conditions resulting in embryo arrest. STUDY FUNDING/COMPETING INTEREST(S): No external funding was obtained for this study. There are no competing interests.


Assuntos
Blastocisto/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Ectogênese , Estresse do Retículo Endoplasmático , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Blastocisto/citologia , Blastocisto/efeitos dos fármacos , Blastocisto/patologia , Sinalização do Cálcio/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Células Cultivadas , Citoplasma/efeitos dos fármacos , Citoplasma/patologia , Ectogênese/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Infertilidade/metabolismo , Infertilidade/patologia , Masculino , Potencial da Membrana Mitocondrial , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/metabolismo , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Recombinantes de Fusão/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/antagonistas & inibidores , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Peça Intermédia do Espermatozoide/metabolismo , Peça Intermédia do Espermatozoide/patologia
11.
Comput Struct Biotechnol J ; 21: 5609-5619, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38047232

RESUMO

Mitochondria are essential organelles that play crucial roles in cellular energy metabolism, calcium signaling and apoptosis. Their importance in tissue homeostasis and stress responses, combined to their ability to transition between various structural and functional states, make them excellent organelles for monitoring cellular health. Quantitative assessment of mitochondrial morphology can therefore provide valuable insights into environmentally-induced cell damage. High-content screening (HCS) provides a powerful tool for analyzing organelles and cellular substructures. We developed a fully automated and miniaturized HCS wet-plus-dry pipeline (MITOMATICS) exploiting mitochondrial morphology as a marker for monitoring cellular health or damage. MITOMATICS uses an in-house, proprietary software (MitoRadar) to enable fast, exhaustive and cost-effective analysis of mitochondrial morphology and its inherent diversity in live cells. We applied our pipeline and big data analytics software to assess the mitotoxicity of selected chemicals, using the mitochondrial uncoupler CCCP as an internal control. Six different pesticides (inhibiting complexes I, II and III of the mitochondrial respiratory chain) were tested as individual compounds and five other pesticides present locally in Occitanie (Southern France) were assessed in combination to determine acute mitotoxicity. Our results show that the assayed pesticides exhibit specific signatures when used as single compounds or chemical mixtures and that they function synergistically to impact mitochondrial architecture. Study of environment-induced mitochondrial damage has the potential to open new fields in mechanistic toxicology, currently underexplored by regulatory toxicology and exposome research. Such exploration could inform health policy guidelines and foster pharmacological intervention, water, air and soil pollution control and food safety.

12.
Mol Biol Evol ; 28(12): 3271-83, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21705382

RESUMO

Insertions or deletions (indels) of amino acids residues have been recognized as an important source of genetic and structural divergence between paralogous Bcl-2 family members. However, these signature sequences have not so far been extensively investigated amongst orthologous Bcl-2 family proteins. Bcl2l10 is an antiapoptotic member of the Bcl-2 family that has evolved rapidly throughout the vertebrate lineage and which shows conserved abundant expression in eggs and oocytes. In this paper, we have unraveled two major sites of divergence between human Bcl2l10 and its vertebrate homologs. The first one provides length variation at the N-terminus (before the BH4 domain) and the second one is located between the predicted α5-α6 pore-forming helices, providing an unprecedented case in the superfamily of helix-bundled pore-forming proteins. These two particular indels were studied phylogenetically and through biochemical and cell biological techniques, including truncation and site-directed mutagenesis. While deletion of the N-terminal extension had no significant functional impact in HeLa cells, our results suggest that the human Bcl2l10 protein evolved a calcium-binding motif in its α5-α6 interhelical region by acquiring critical negatively charged residues. Considering the reliance of female eggs on calcium-dependent proteins and calcium-regulated processes and the exceptional longevity of oocytes in the primate lineage, we propose that this microstructural variation may be an adaptive feature associated with high maternal expression of this Bcl-2 family member.


Assuntos
Cálcio/metabolismo , Evolução Molecular , Mutação INDEL , Proteínas Proto-Oncogênicas c-bcl-2/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Apoptose/genética , Sequência de Bases , Linhagem Celular , Bases de Dados Genéticas , Feminino , Variação Genética , Células HeLa , Humanos , Dados de Sequência Molecular , Mutagênese Insercional/genética , Oócitos , Estrutura Terciária de Proteína , Alinhamento de Sequência , Deleção de Sequência
13.
Reproduction ; 141(5): 549-61, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21339285

RESUMO

In women, up to 99.9% of the oocyte stockpile formed during fetal life is decimated by apoptosis. Apoptotic features are also detected in human preimplantation embryos both in vivo and in vitro. Despite the important consequences of cell death processes to oocyte competence and early embryonic development, little is known about its genetic and molecular control. B cell lymphoma-2 (BCL2) family proteins are major regulators of cell death and survival. Here, we present a literature review on BCL2 family expression and protein distribution in human and animal oocytes and early embryos. Most of the studies focused on the expression of two antagonistic members: the founding and survival family member BCL2 and its proapoptotic homolog BAX. However, recent transcriptomic analyses have identified novel candidate genes related to oocyte and/or early embryonic viability (such as BCL2L10) or commitment to apoptosis (e.g. BIK). Interestingly, some BCL2 proteins appear to be differentially distributed at the subcellular level during oocyte maturation and early embryonic development, a process probably linked to the functional compartmentalization of the ooplasm and blastomere. Assessment of BCL2 family involvement in regulating the survival of human oocytes and embryos may be of particular value for diagnosis and assisted reproductive technology. We suggest that implications of not only aberrant gene expression but also abnormal subcellular protein redistribution should be established in pathological conditions resulting in infertility.


Assuntos
Blastocisto/metabolismo , Oócitos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Animais , Blastocisto/patologia , Morte Celular , Sobrevivência Celular , Feminino , Fertilidade , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Infertilidade/genética , Infertilidade/metabolismo , Infertilidade/fisiopatologia , Oócitos/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética
14.
Transl Psychiatry ; 11(1): 527, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645790

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that is associated with unique changes in mitochondrial metabolism, including elevated respiration rates and morphological alterations. We examined electron transport chain (ETC) complex activity in fibroblasts derived from 18 children with ASD as well as mitochondrial morphology measurements in fibroblasts derived from the ASD participants and four typically developing controls. In ASD participants, symptoms severity was measured by the Social Responsiveness Scale and Aberrant Behavior Checklist. Mixed-model regression demonstrated that alterations in mitochondrial morphology were associated with both ETC Complex I+III and IV activity as well as the difference between ETC Complex I+III and IV activity. The subgroup of ASD participants with relative elevation in Complex IV activity demonstrated more typical mitochondrial morphology and milder ASD related symptoms. This study is limited by sample size given the invasive nature of obtaining fibroblasts from children. Furthermore, since mitochondrial function is heterogenous across tissues, the result may be specific to fibroblast respiration. Previous studies have separately described elevated ETC Complex IV activity and changes in mitochondrial morphology in cells derived from children with ASD but this is the first study to link these two findings in mitochondrial metabolism. The association between a difference in ETC complex I+III and IV activity and normal morphology suggests that mitochondrial in individuals with ASD may require ETC uncoupling to function optimally. Further studies should assess the molecular mechanisms behind these unique metabolic changes.Trial registration: Protocols used in this study were registered in clinicaltrials.gov as NCT02000284 and NCT02003170.


Assuntos
Transtorno do Espectro Autista , Transtorno do Espectro Autista/metabolismo , Transporte de Elétrons , Complexo I de Transporte de Elétrons , Humanos , Mitocôndrias/metabolismo , Oxirredução
16.
Methods Mol Biol ; 1877: 23-43, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30535996

RESUMO

BCL-2 proteins correspond to a structurally, functionally, and phylogenetically heterogeneous group of regulators that play crucial roles in the life and death of animal cells. Some of these regulators also represent therapeutic targets in human diseases including cancer. In the omics era, there is great need for easy data retrieval and fast analysis of the molecular players involved in cell death. In this chapter, we present generic and specific computational resources (such as the reference database BCL2DB) as well as bioinformatics tools that can be used to investigate BCL-2 homologs and BH3-only proteins.


Assuntos
Proteínas Proto-Oncogênicas c-bcl-2/genética , Animais , Morte Celular/genética , Biologia Computacional/métodos , Bases de Dados Genéticas , Bases de Dados de Proteínas , Doença/genética , Humanos
17.
CNS Neurosci Ther ; 25(7): 887-902, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31197948

RESUMO

The underlying molecular basis for neurodevelopmental or neuropsychiatric disorders is not known. In contrast, mechanistic understanding of other brain disorders including neurodegeneration has advanced considerably. Yet, these do not approach the knowledge accrued for many cancers with precision therapeutics acting on well-characterized targets. Although the identification of genes responsible for neurodevelopmental and neuropsychiatric disorders remains a major obstacle, the few causally associated genes are ripe for discovery by focusing efforts to dissect their mechanisms. Here, we make a case for delving into mechanisms of the poorly characterized human KCTD gene family. Varying levels of evidence support their roles in neurocognitive disorders (KCTD3), neurodevelopmental disease (KCTD7), bipolar disorder (KCTD12), autism and schizophrenia (KCTD13), movement disorders (KCTD17), cancer (KCTD11), and obesity (KCTD15). Collective knowledge about these genes adds enhanced value, and critical insights into potential disease mechanisms have come from unexpected sources. Translation of basic research on the KCTD-related yeast protein Whi2 has revealed roles in nutrient signaling to mTORC1 (KCTD11) and an autophagy-lysosome pathway affecting mitochondria (KCTD7). Recent biochemical and structure-based studies (KCTD12, KCTD13, KCTD16) reveal mechanisms of regulating membrane channel activities through modulation of distinct GTPases. We explore how these seemingly varied functions may be disease related.


Assuntos
Transtornos do Neurodesenvolvimento/metabolismo , Proteínas/metabolismo , Animais , Humanos , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/metabolismo , Transtornos do Neurodesenvolvimento/genética , Proteínas/genética
18.
Cell Death Differ ; 26(5): 902-917, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30042493

RESUMO

BCL2A1 is an anti-apoptotic member of the BCL-2 family that contributes to chemoresistance in a subset of tumors. BCL2A1 has a short half-life due to its constitutive processing by the ubiquitin-proteasome system. This constitutes a major tumor-suppressor mechanism regulating BCL2A1 function. However, the enzymes involved in the regulation of BCL2A1 protein stability are currently unknown. Here, we provide the first insight into the regulation of BCL2A1 ubiquitination. We present evidence that TRIM28 is an E3 ubiquitin-ligase for BCL2A1. Indeed, endogenous TRIM28 and BCL2A1 bind to each other at the mitochondria and TRIM28 knock-down decreases BCL2A1 ubiquitination. We also show that TRIM17 stabilizes BCL2A1 by blocking TRIM28 from binding and ubiquitinating BCL2A1, and that GSK3 is involved in the phosphorylation-mediated inhibition of BCL2A1 degradation. BCL2A1 and its close relative MCL1 are thus regulated by common factors but with opposite outcome. Finally, overexpression of TRIM28 or knock-out of TRIM17 reduced BCLA1 protein levels and restored sensitivity of melanoma cells to BRAF-targeted therapy. Therefore, our data describe a molecular rheostat in which two proteins of the TRIM family antagonistically regulate BCL2A1 stability and modulate cell death.


Assuntos
Apoptose/genética , Antígenos de Histocompatibilidade Menor/genética , Neoplasias/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas com Motivo Tripartido/genética , Proteína 28 com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética , Morte Celular/genética , Linhagem Celular Tumoral , Doxiciclina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/genética , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fosforilação/genética , Complexo de Endopeptidases do Proteassoma/genética , Ligação Proteica/genética , Estabilidade Proteica , Proteólise/efeitos dos fármacos , Ubiquitinação/genética
19.
Biochimie ; 90(4): 563-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17988782

RESUMO

Single nucleotide polymorphisms (SNPs), which are the most abundant form of genetic variations in numerous organisms, have emerged as important tools for the study of complex genetic traits and deciphering of genome evolution. High-throughput genome sequencing projects worldwide provide an unprecedented opportunity for whole-genome SNP analysis in a variety of species. To facilitate SNP discovery in vertebrates, we have developed a web-based, user-friendly, and fully automated application, DigiPINS, for genome-wide identification of exonic SNPs from EST data. Currently, the database can be used to the mining of exonic SNPs in six complete genomes (Homo sapiens, Mus musculus, Rattus norvegicus, Canis familiaris, Gallus gallus and Danio rerio). In addition to providing information on sequence conservation, DigiPINS allows compilation of comprehensive sets of polymorphisms within cancer candidate genes or identification of novel cancer markers, making it potentially useful for cancer association studies. The DigiPINS server is available via the internet at http://pbil.univ-lyon1.fr/gem/DigiPINS/query_DigiPINS.php.


Assuntos
Bases de Dados Genéticas , Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Software , Sequência de Aminoácidos , Animais , Sequência de Bases , Biomarcadores , Etiquetas de Sequências Expressas , Genoma , Humanos , Armazenamento e Recuperação da Informação/métodos , Internet , Dados de Sequência Molecular , Análise de Sequência de DNA , Interface Usuário-Computador
20.
Science ; 360(6395)2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29930109

RESUMO

Shlezinger et al (Reports, 8 September 2017, p. 1037) report that the common fungus Aspergillus fumigatus, a cause of aspergillosis, undergoes caspase-dependent apoptosis-like cell death triggered by lung neutrophils. However, the technologies they used do not provide reliable evidence that fungal cells die via a protease signaling cascade thwarted by a fungal caspase inhibitor homologous to human survivin.


Assuntos
Aspergilose/imunologia , Aspergillus fumigatus/imunologia , Apoptose/imunologia , Morte Celular , Humanos , Pulmão/imunologia
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