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:In acute cold stress in mammals, JMJD1A, an H3K9 demethylase, up-regulates thermogenic gene expressions through β-adrenergic signaling in brown adipose tissue (BAT). Aside BAT-driven thermogenesis, mammals also have another mechanism to cope with long-term cold stress by inducing the browning of subcutaneous white adipose tissue (scWAT). Here, we show that this occurs through a two-step process that requires both β-adrenergic dependent phosphorylation of S265 and demethylation of H3K9me2 by JMJD1A. The histone demethylation independent acute Ucp1 induction in BAT and demethylation dependent chronic Ucp1 expression in beige-scWAT provide complementary molecular mechanisms to ensure an ordered transition between acute and chronic adaptation to cold stress. JMJD1A mediates two major signaling pathways, namlely β-adrenergic receptor and PPARγ activation, via PRDM16-PPARγ-P-JMJD1A complex for beige adipogenesis.
Project description:In acute cold stress in mammals, JMJD1A, an H3K9 demethylase, up-regulates thermogenic gene expressions through β-adrenergic signaling in brown adipose tissue (BAT). Aside BAT-driven thermogenesis, mammals also have another mechanism to cope with long-term cold stress by inducing the browning of subcutaneous white adipose tissue (scWAT). Here, we show that this occurs through a two-step process that requires both β-adrenergic dependent phosphorylation of S265 and demethylation of H3K9me2 by JMJD1A. The histone demethylation independent acute Ucp1 induction in BAT and demethylation dependent chronic Ucp1 expression in beige-scWAT provide complementary molecular mechanisms to ensure an ordered transition between acute and chronic adaptation to cold stress. JMJD1A mediates two major signaling pathways, namlely β-adrenergic receptor and PPARγ activation, via PRDM16-PPARγ-P-JMJD1A complex for beige adipogenesis.
Project description:Genome-wide analysis of JMJD1A and PPARγ binding in immortalized, differentiated preadipocytes derived from inguinal subcutaneous white adipose tissue.
Project description:Mitochondria play a vital role in non-shivering thermogenesis in both brown and subcutaneous white adipose tissues (BAT and scWAT, respectively). However, specific regulatory mechanisms driving mitochondrial function in these tissues have been unclear. Here we demonstrate that prolonged activation of β-adrenergic signaling induces epigenetic modifications in scWAT, specifically targeting the enhancers for the mitochondria master regulator genes Pgc1a/b. This is mediated at least partially through JMJD1A, a histone demethylase that in response to β-adrenergic signals, facilitates H3K9 demethylation of the Pgc1a/b enhancers, promoting mitochondrial biogenesis and the formation of beige adipocytes. Disruption of demethylation activity of JMJD1A in mice impairs activation of Pgc1a/b driven mitochondrial biogenesis and limits scWAT beiging, contributing to reduced energy expenditure, obesity, insulin resistance, and metabolic disorders. Notably, JMJD1A demethylase activity is not required for Pgc1a/b dependent thermogenic capacity of BAT especially during acute cold stress, emphasizing the importance of scWAT thermogenesis in overall energy metabolism.
Project description:Mitochondria play a vital role in non-shivering thermogenesis in both brown and subcutaneous white adipose tissues (BAT and scWAT, respectively). However, specific regulatory mechanisms driving mitochondrial function in these tissues have been unclear. Here we demonstrate that prolonged activation of β-adrenergic signaling induces epigenetic modifications in scWAT, specifically targeting the enhancers for the mitochondria master regulator genes Pgc1a/b. This is mediated at least partially through JMJD1A, a histone demethylase that in response to β-adrenergic signals, facilitates H3K9 demethylation of the Pgc1a/b enhancers, promoting mitochondrial biogenesis and the formation of beige adipocytes. Disruption of demethylation activity of JMJD1A in mice impairs activation of Pgc1a/b driven mitochondrial biogenesis and limits scWAT beiging, contributing to reduced energy expenditure, obesity, insulin resistance, and metabolic disorders. Notably, JMJD1A demethylase activity is not required for Pgc1a/b dependent thermogenic capacity of BAT especially during acute cold stress, emphasizing the importance of scWAT thermogenesis in overall energy metabolism.
Project description:Transcript data from subcutaneous white adipose tissue (scWAT) from fasted-state male BXD strains on chow or high fat diet We used microarrays to compare the subcutaneous white adipose tissue (scWAT) expression differences across the BXD strain family and across two diverse diets
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.