Project description:Matrix induced effects on gene expression in HeLa and MDA-MB-231 cells Tissue homeostasis is dependent on the spatially controlled localization of specific cell types and the correct composition of the extracellular stroma. While the role of the cancer stroma in tumor progression has been well characterized, the specific contribution of the matrix itself is unknown. Furthermore, the mechanisms enabling normal – not cancer – stroma to provide tumor suppressive signals and act as an anti-tumorigenic barrier are poorly understood. Here, we show that extracellular matrix (ECM) generated by normal fibroblasts (NFs) is softer than CAF-matrix and it is the physical and structural features of NF-generated matrix that regulate cancer cell proliferation . We find that normal stromal ECM triggers downregulation and nuclear exit of the histone demethylase JMJD1a resulting in the epigenetic growth restriction of carcinoma cells. Interestingly, JMJD1a positively regulates transcription of many target genes, including YAP/TAZ, and thus therefore gene expression in stiffness-dependent manner. Thus normal stromal restricts cancer cell proliferation through JMJD1a-dependent modulation of gene expression.
Project description:Protein kinase A promotes beige adipogenesis downstream from β-adrenergic receptor signaling by phosphorylating proteins, including histone H3 lysine 9 (H3K9) demethylase JMJD1A. To ensure homeostasis, this process needs to be reversible however, this step is not well understood. We show that myosin phosphatase target subunit 1- protein phosphatase 1β (MYPT1-PP1β) phosphatase activity is inhibited via PKA-dependent phosphorylation, which increases phosphorylated JMJD1A and beige adipogenesis. Mechanistically, MYPT1-PP1β depletion resulted in JMJD1A-mediated H3K9 demethylation and activation of the Ucp1 enhancer/promoter regions. Interestingly, MYPT1-PP1β also dephosphorylates myosin light chain which regulates actomyosin tension-mediated activation of YAP/TAZ which directly stimulates Ucp1 gene expression. Preadipocyte specific Mypt1 deficiency increases cold tolerance with higher Ucp1 levels in subcutaneous white adipose tissues compared to control mice, confirming this regulatory mechanism in vivo. Thus, we have uncovered new regulatory cross-talk involved in beige adipogenesis that coordinates epigenetic regulation with direct activation of the mechano-sensitive YAP/TAZ transcriptional co-activators.
Project description:Protein kinase A promotes beige adipogenesis downstream from β-adrenergic receptor signaling by phosphorylating proteins, including histone H3 lysine 9 (H3K9) demethylase JMJD1A. To ensure homeostasis, this process needs to be reversible however, this step is not well understood. We show that myosin phosphatase target subunit 1- protein phosphatase 1β (MYPT1-PP1β) phosphatase activity is inhibited via PKA-dependent phosphorylation, which increases phosphorylated JMJD1A and beige adipogenesis. Mechanistically, MYPT1-PP1β depletion resulted in JMJD1A-mediated H3K9 demethylation and activation of the Ucp1 enhancer/promoter regions. Interestingly, MYPT1-PP1β also dephosphorylates myosin light chain which regulates actomyosin tension-mediated activation of YAP/TAZ which directly stimulates Ucp1 gene expression. Preadipocyte specific Mypt1 deficiency increases cold tolerance with higher Ucp1 levels in subcutaneous white adipose tissues compared to control mice, confirming this regulatory mechanism in vivo. Thus, we have uncovered new regulatory cross-talk involved in beige adipogenesis that coordinates epigenetic regulation with direct activation of the mechano-sensitive YAP/TAZ transcriptional co-activators.
Project description:Protein kinase A phosphorylates proteins including histone H3 lysine 9 (H3K9) demethylase JMJD1A to facilitate beige adipogenesis upon β-adrenergic receptor (β-AR) activation, however, phosphatase(s) that antagonizes phosphorylation to inhibit beige adipogenesis is incompletely understood. Here we show that MYPT1-PP1β is a phosphatase that negatively regulates beige adipogenesis via dephosphorylation of pS265-JMJD1A and myosin regulatory light chain. Upon β-AR activation, MYPT1-PP1β is inhibited via T694 phosphorylation of MYPT1, facilitating phosphorylation of JMJD1A and beige adipogenesis under cold stress. Depletion of MYPT1-PP1β induces Ucp1 by orchestrating JMJD1A-mediated H3K9 demethylation and actomyosin-tension mediated YAP/TAZ activation. This induction of Ucp1 is abrogated in adipocytes expressing catalytically dead JMJD1A mutant, indicating that the coordinated epigenetic and transcriptional mechanisms are essential for beige adipogenesis. We also show that preadipocytes specific Mypt1 deficient mice exhibit higher cold tolerance with higher Ucp1 levels in subcutaneous white adipose tissues compared to control mice confirming its role at animal levels.
Project description:The histone demethylase JMJD1A(Jumoji domain containing 1A) is overexpressed in multiple cancers and promotes cancer progression. However, the role and mechanism of JMJD1A in gastric cancer remains poorly understood.Here, we found that JMJD1A could suppress gastric cancer cell proliferation, migration, invasion and xenograft tumor growth. Using RNA sequencing, we identified RUNX3 as a novel target gene of JMJD1A.
Project description:Histone H3 lysine 9 (H3K9) methylation is an epigenetic mark of transcriptionally repressed chromatin. During mammalian development, H3K9 methylation levels seem to be spatiotemporally regulated by the opposing activities of methyltransferases and demethylases to govern correct gene expression. However, the combination(s) of H3K9 methyltransferase(s) and demethylase(s) that contribute to this regulation and the genes regulated by them remain unclear. Herein, we demonstrate the essential roles of H3K9 demethylases Jmjd1a and Jmjd1b in the embryogenesis and viability control of embryonic stem (ES) cells. Mouse embryos lacking Jmjd1a/Jmjd1b died after implantation. Depletion of Jmjd1a/Jmjd1b in mouse ES cells induced rapid cell death accompanied with a massive increase in H3K9 methylation. Jmjd1a/Jmjd1b depletion induced an increase in H3K9 methylation in the gene-rich regions of the chromosomes, indicating that Jmjd1a/Jmjd1b removes H3K9 methylation marks in the euchromatin. Importantly, the additional disruption of the H3K9 methyltransferase G9a in a Jmjd1a/Jmjd1b-deficient background rescued not only the H3K9 hypermethylation phenotype but also the cell death phenotype. We also found that Jmjd1a/Jmjd1b removes H3K9 methylation marks deposited by G9a in the Oct4 and Ccnd1 loci to activate transcription. In conclusion, Jmjd1a/Jmjd1b ensures ES cell viability by antagonizing G9a-mediated H3K9 hypermethylation in the gene-rich euchromatin.
Project description:The current studies show that JMJD1A is phosphorylated at S265 by protein kinase A (PKA), and this is pivotal to activate expression of the b1-adrenergic receptor gene (Adrb1) and downstream targets including Ucp1. Phosphorylation of JMJD1A increases its interaction with the SWI/SNF nucleosome remodeling complex and DNA-bound PPARg. This complex conferred b-adrenergic-induced JMJD1A recruitment to target sites throughout the genome. Phospho-JMJD1A also facilitated long-range chromatin looping to recruit PPARg-bound distal-enhancers, SWI/SNF, and RNA polymerase close to the Adrb1 locus to activate transcription. Mutation of the PKA-phosphorylation site on JMJD1A abolished interactions with SWI/SNF without affecting demethylase activity suggesting the two functions are independent of each other. Our results show that JMJD1A demethylase is also a signal-sensing scaffold that regulates cAMP-responsive transcription via interactions with SWI/SNF and hormone stimulated higher-order chromatin conformational changes. There are 3 samples analyzed. No duplication from each sample. Isoproterenol stimulation at 0hr is used as the relative to fold change in manuscript.
Project description:The Hypoxia-Inducible Factors induce the expression of the histone demethylases JMJD1A (KDM3A) and JMJD2B (KDM4B), linking the hypoxic tumor microenvironment to epigenetic mechanisms that may foster tumor progression. Using transcript profiling, we have identified genes that are regulated in RCC4 with siRNA-mediated knockdown of JMJD1A and JMJD2B. This dataset includes expression data obtained from renal cell Carcinoma being loss or mutation of the von Hippel-Lindau (VHL) tumor suppressor gene combination with siRNA-mediated knockdown of histone demethylases JMJD1A and JMJD2B.