Similar Datasets
Project description:Skeletal muscle possesses remarkable regenerative ability owing to the resident muscle stem cells (MuSCs). A prominent feature of quiescent MuSCs is a high content of heterochromatin. However, little is known about the mechanisms by which heterochromatin is maintained in MuSCs. We found that the mammalian Hairless (Hr) gene is expressed in quiescent MuSCs. Using a mouse model in which Hr can be specifically ablated in MuSCs, we demonstrate that Hr expression is critical for MuSC function and muscle regeneration. We show that Hr is a histone demethylase antagonist that preserves Histone 3 Lysine 9 trimethylation (H3K9me3) and maintains heterochromatin structure. Loss of Hr results in reduced H3K9me3 levels, reduced heterochromatin, increased susceptibility of MuSCs to genotoxic stress, and the accumulation of DNA damage. Our study not only elucidates the molecular mechanism by which Hr regulates histone demethylases, but also demonstrates the importance of heterochromatin maintenance in stem cell function.
2021-09-09 | GSE132220 | GEO
Project description:Skeletal muscle possesses remarkable regenerative ability owing to the resident muscle stem cells (MuSCs). A prominent feature of quiescent MuSCs is a high content of heterochromatin. However, little is known about the mechanisms by which heterochromatin is maintained in MuSCs. We found that the mammalian Hairless (Hr) gene is expressed in quiescent MuSCs. Using a mouse model in which Hr can be specifically ablated in MuSCs, we demonstrate that Hr expression is critical for MuSC function and muscle regeneration. We show that Hr is a histone demethylase antagonist that preserves Histone 3 Lysine 9 trimethylation (H3K9me3) and maintains heterochromatin structure. Loss of Hr results in reduced H3K9me3 levels, reduced heterochromatin, increased susceptibility of MuSCs to genotoxic stress, and the accumulation of DNA damage. Our study not only elucidates the molecular mechanism by which Hr regulates histone demethylases, but also demonstrates the importance of heterochromatin maintenance in stem cell function.
2021-09-09 | GSE132189 | GEO
Project description:Hairless regulates heterochromatin maintenance and muscle stem cell function as a histone demethylase antagonist
| PRJNA546609 | ENA
Project description:Hairless regulates heterochromatin maintenance and muscle stem cell function as a histone demethylase antagonist [RNA-seq]
| PRJNA546281 | ENA
Project description:Hairless regulates heterochromatin maintenance and muscle stem cell function as a histone demethylase antagonist (ChIPseq, ATACseq)
| PRJNA546535 | ENA
Project description:The hairless (HR) protein contains a Jumonji C (JmjC) domain that is conserved among a family of proteins with histone demethylase (HDM) activity. To test whether HR possesses HDM activity, we performed a series of in vitro demethylation assays, which demonstrated that HR can demethylate monomethylated or dimethylated histone H3 lysine 9 (H3K9me1 or me2). Moreover, ectopic expression of wild-type HR, but not JmjC-mutant HR, led to pronounced demethylation of H3K9 in cultured human HeLa cells. We also show that two missense mutations in HR, which we and others described in patients with atrichia with papular lesions, abolished the demethylase activity of HR, demonstrating the role of HR demethylase activity in human disease. By ChIP-Seq analysis, we identified multiple new HR target genes, many of which play important roles in epidermal development, neural function, and transcriptional regulation, consistent with the predicted biological functions of HR. Our findings demonstrate for the first time that HR is a H3K9 demethylase that regulates epidermal homeostasis via direct control of its target genes.
| S-EPMC3963012 | biostudies-literature
Project description:Ovarian cancer is a highly deadly disease, which is often diagnosed at a late stage with metastases. However, most ovarian cancers relapse after surgery combined with platinum-based chemotherapy. Cancer stem cells (CSCs) are stem-like cells that possess high tumorigenic capability and display higher resistant capability against current therapies. However, our knowledge of ovarian CSCs and their molecular mechanism remains sparse. In the current study, we found that KDM4C, a histone demethylase, was required for ovarian cancer stem cell (CSC) maintenance. Depletion of KDM4C significantly reduced the CSC population and sphere formation in vitro. Moreover, we found that KDM4C can regulate the expression of stem cell factor OCT-4 via binding to its promoter. These data indicate that KDM4C is relevant for ovarian CSC maintenance and underscore its importance as a potential therapeutic target.
| S-EPMC7475738 | biostudies-literature
Project description:Loss-of-function mutations in the histone demethylases KDM5A, KDM5B, or KDM5C are found in intellectual disability (ID) and autism spectrum disorders (ASD) patients. Here, we use the model organism Drosophila melanogaster to delineate how KDM5 contributes to ID and ASD. We show that reducing KDM5 causes intestinal barrier dysfunction and changes in social behavior that correlates with compositional changes in the gut microbiota. Therapeutic alteration of the dysbiotic microbiota through antibiotic administration or feeding with a probiotic Lactobacillus strain partially rescues the behavioral, lifespan, and cellular phenotypes observed in kdm5-deficient flies. Mechanistically, KDM5 was found to transcriptionally regulate component genes of the immune deficiency (IMD) signaling pathway and subsequent maintenance of host-commensal bacteria homeostasis in a demethylase-dependent manner. Together, our study uses a genetic approach to dissect the role of KDM5 in the gut-microbiome-brain axis and suggests that modifying the gut microbiome may provide therapeutic benefits for ID and ASD patients.
| S-EPMC6749836 | biostudies-literature
Project description:Epigenetic mechanisms, in particular the enzymatic modification of histones, are a crucial element of cell differentiation, a regulated process that allows a precursor cell basically to turn into a different cell type while maintaining the same genetic equipment. We have previously described that the promoters of adipogenic genes display significant levels of dimethylation at the Lys(4) of histone H3 (H3K4) in preadipocytes, where these genes are still silenced, thus maintaining the chromatin of the precursor cell in a receptive state. Here, we show that the expression of several histone demethylases and methyltransferases increases during adipogenesis, suggesting an important role for these proteins in this process. Knockdown of the H3K4/K9 demethylase LSD1 results in markedly decreased differentiation of 3T3-L1 preadipocytes. This outcome is associated with decreased H3K4 dimethylation and increased H3K9 dimethylation at the promoter of transcription factor cebpa, whose expression must be induced >200-fold upon stimulation of differentiation. Thus, our data suggest that LSD1 acts to maintain a permissive state of the chromatin in this promoter by opposing the action of a H3K9 methyltransferase. Knockdown of H3K9 methyltransferase SETDB1 produced the opposite results, by decreasing H3K9 dimethylation and increasing H3K4 dimethylation levels at the cebpa promoter and favoring differentiation. These findings indicate that the histone methylation status of adipogenic genes as well as the expression and function of the proteins involved in its maintenance play a crucial role in adipogenesis.
| S-EPMC2943311 | biostudies-literature
Project description:Trophoblast stem cell (TSC) is crucial to the formation of placenta in mammals. Histone demethylase JMJD2 (also known as KDM4) family proteins have been previously shown to support self-renewal and differentiation of stem cells. However, their roles in the context of the trophoblast lineage remain unclear. Here, we find that knockdown of Jmjd2b resulted in differentiation of TSCs, suggesting an indispensable role of JMJD2B/KDM4B in maintaining the stemness. Through the integration of transcriptome and ChIP-seq profiling data, we show that JMJD2B is associated with a loss of H3K36me3 in a subset of embryonic lineage genes which are marked by H3K9me3 for stable repression. By characterizing the JMJD2B binding motifs and other transcription factor binding datasets, we discover that JMJD2B forms a protein complex with AP-2 family transcription factor TFAP2C and histone demethylase LSD1. The JMJD2B-TFAP2C-LSD1 complex predominantly occupies active gene promoters, whereas the TFAP2C-LSD1 complex is located at putative enhancers, suggesting that these proteins mediate enhancer-promoter interaction for gene regulation. We conclude that JMJD2B is vital to the TSC transcriptional program and safeguards the trophoblast cell fate via distinctive protein interactors and epigenetic targets.
| S-EPMC7806742 | biostudies-literature