Similar Datasets
Project description:Members of the Chromodomain-Helicase-DNA binding (CHD) protein family are chromatin remodelers critically implicated in human pathologies. CHD6 is the least studied member of this family, and we were motivated to dissect its in-cell roles by discovering a mutated CHD6 allele in a patient suffering from the rare Hallermann-Streiff premature aging syndrome (HSS). We generated isogenic iPSC lines carrying (or not) this single point mutation in the CHD6 SANT/SLIDE domain, which allow studying HSS-relevant cell identities. Using these lines, we show for the first time that CHD6 binds the promoters of a cohort of autophagy and stress response genes across cell types. This CHD6 mutation impairs its ability to recruit co-factors and regulate genes in response to DNA damage and autophagy stimulation, thus leading to accumulation of unresolved DNA damage burden. By combining genomics and functional assays, we describe a molecular mechanism underlying chromatin control of autophagic flux and genotoxic stress surveillance that is broadly applicable to human cell types and can explain HSS establishment.
2021-02-19 | GSE136057 | GEO
Project description:Members of the Chromodomain-Helicase-DNA binding (CHD) protein family are chromatin remodelers critically implicated in human pathologies. CHD6 is the least studied member of this family, and we were motivated to dissect its in-cell roles by discovering a mutated CHD6 allele in a patient suffering from the rare Hallermann-Streiff premature aging syndrome (HSS). We generated isogenic iPSC lines carrying (or not) this single point mutation in the CHD6 SANT/SLIDE domain, which allow studying HSS-relevant cell identities. Using these lines, we show for the first time that CHD6 binds the promoters of a cohort of autophagy and stress response genes across cell types. This CHD6 mutation impairs its ability to recruit co-factors and regulate genes in response to DNA damage and autophagy stimulation, thus leading to accumulation of unresolved DNA damage burden. By combining genomics and functional assays, we describe a molecular mechanism underlying chromatin control of autophagic flux and genotoxic stress surveillance that is broadly applicable to human cell types and can explain HSS establishment.
2021-02-19 | GSE135832 | GEO
Project description:Impaired CHD6 function links misregulation of autophagy and DNA damage response to premature ageing
| PRJNA675606 | ENA
Project description:Impaired CHD6 function links misregulation of autophagy and DNA damage response to premature ageing [RNA-Seq]
| PRJNA560229 | ENA
Project description:Impaired CHD6 function links misregulation of autophagy and DNA damage response to premature ageing [ChIP-Seq]
| PRJNA561142 | ENA
Project description:Members of the chromodomain-helicase-DNA binding (CHD) protein family are chromatin remodelers implicated in human pathologies, with CHD6 being one of its least studied members. We discovered a de novo CHD6 missense mutation in a patient clinically presenting the rare Hallermann-Streiff syndrome (HSS). We used genome editing to generate isogenic iPSC lines and model HSS in relevant cell types. By combining genomics with functional in vivo and in vitro assays, we show that CHD6 binds a cohort of autophagy and stress response genes across cell types. The HSS mutation affects CHD6 protein folding and impairs its ability to recruit co-remodelers in response to DNA damage or autophagy stimulation. This leads to accumulation of DNA damage burden and senescence-like phenotypes. We therefore uncovered a molecular mechanism explaining HSS onset via chromatin control of autophagic flux and genotoxic stress surveillance.
| S-EPMC8140133 | biostudies-literature
Project description:Cell survival after oxidative DNA damage requires signaling, repair and transcriptional events often enabled by nucleosome displacement, exchange or removal by chromatin remodeling enzymes. Here, we show that Chromodomain Helicase DNA-binding protein 6 (CHD6), distinct to other CHD enzymes, is stabilized during oxidative stress via reduced degradation. CHD6 relocates rapidly to DNA damage in a manner dependent upon oxidative lesions and a conserved N-terminal poly(ADP-ribose)-dependent recruitment motif, with later retention requiring the double chromodomain and central core. CHD6 ablation increases reactive oxygen species persistence and impairs anti-oxidant transcriptional responses, leading to elevated DNA breakage and poly(ADP-ribose) induction that cannot be rescued by catalytic or double chromodomain mutants. Despite no overt epigenetic or DNA repair abnormalities, CHD6 loss leads to impaired cell survival after chronic oxidative stress, abnormal chromatin relaxation, amplified DNA damage signaling and checkpoint hypersensitivity. We suggest that CHD6 is a key regulator of the oxidative DNA damage response.
| S-EPMC6335469 | biostudies-literature
Project description:Ageing appears to be a nearly universal feature of life, ranging from unicellular microorganisms to humans. Longevity depends on the maintenance of cellular functionality, and an organism's ability to respond to stress has been linked to functional maintenance and longevity. Stress response pathways might indeed become therapeutic targets of therapies aimed at extending the healthy lifespan. Various progeroid syndromes have been linked to genome instability, indicating an important causal role of DNA damage accumulation in the ageing process and the development of age-related pathologies. Recently, non-cell-autonomous mechanisms including the systemic consequences of cellular senescence have been implicated in regulating organismal ageing. We discuss here the role of cellular and systemic mechanisms of ageing and their role in ageing-associated diseases.
| S-EPMC6893400 | biostudies-literature
Project description:Manganese is an essential trace element, whose intracellular levels need to be carefully regulated. Mn(2+) acts as a cofactor for many enzymes and excess of Mn(2+) is toxic. Alterations in Mn(2+) homeostasis affect metabolic functions and mutations in the human Mn(2+)/Ca(2+) transporter ATP2C1 have been linked to Hailey-Hailey disease. By deletion of the yeast orthologue PMR1 we have studied the impact of Mn(2+) on cell cycle progression and show that an excess of cytosolic Mn(2+) alters S-phase transit, induces transcriptional up-regulation of cell cycle regulators, bypasses the need for S-phase cell cycle checkpoints and predisposes to genomic instability. On the other hand, we find that depletion of the Golgi Mn(2+) pool requires a functional morphology checkpoint to avoid the formation of polyploid cells.
| S-EPMC3365726 | biostudies-literature
Project description:Cardiomyocyte proteostasis is mediated by the ubiquitin/proteasome system (UPS) and autophagy/lysosome system and is fundamental for cardiac adaptation to both physiologic (e.g., exercise) and pathologic (e.g., pressure overload) stresses. Both the UPS and autophagy/lysosome system exhibit reduced efficiency as a consequence of aging, and dysfunction in these systems is associated with cardiomyopathies. The muscle-specific ubiquitin ligase atrogin-1 targets signaling proteins involved in cardiac hypertrophy for degradation. Here, using atrogin-1 KO mice in combination with in vivo pulsed stable isotope labeling of amino acids in cell culture proteomics and biochemical and cellular analyses, we identified charged multivesicular body protein 2B (CHMP2B), which is part of an endosomal sorting complex (ESCRT) required for autophagy, as a target of atrogin-1-mediated degradation. Mice lacking atrogin-1 failed to degrade CHMP2B, resulting in autophagy impairment, intracellular protein aggregate accumulation, unfolded protein response activation, and subsequent cardiomyocyte apoptosis, all of which increased progressively with age. Cellular proteostasis alterations resulted in cardiomyopathy characterized by myocardial remodeling with interstitial fibrosis, with reduced diastolic function and arrhythmias. CHMP2B downregulation in atrogin-1 KO mice restored autophagy and decreased proteotoxicity, thereby preventing cell death. These data indicate that atrogin-1 promotes cardiomyocyte health through mediating the interplay between UPS and autophagy/lysosome system and its alteration promotes development of cardiomyopathies.
| S-EPMC4038560 | biostudies-literature