Project description:We use ChIP-seq to discover the genome-wide sites of acetylation of lysine 56 of the histone H3 (H3K56), which is a target of three histone modifying enzymes with known roles in diabetes and insulin resistance, in human adipocytes derived from mesenchymal stem cells. Surprisingly, we find that a very large fraction of genes show some level of acetylation on H3K56, but the highest levels of acetylation are associated with genes previously reported to be involved in type 2 diabetes. Using computational methods, we propose that the transcription factor E2F4 may be involved in recruiting histone modifying enzymes to these sites. We confirm this prediction by measuring the binding of E2F4 using ChIP-seq. We also examine the binding of two other proteins using ChIP-Seq: HSF-1 and C/EBPM-NM-1M-BM- . HSF-1 is a master regulator of stress responses, and is a target of the same histone modifiers as H3K56. We find a high degree of overlap between HSF-1 binding and H3K56 acetylation even in cells that are not stressed. By contrast, C/EBPM-NM-1M-BM- , which is not known to be modified by these enzymes, shows much less overlap with the sites of H3K56 acetylation. Our results represent the first mapping of the regulatory code of human adipocytes. Examination of H3K56 acetylation sites and E2F4,C/EBPM-NM-1 and HSF-1 binding sites in human adipocytes.
Project description:We use ChIP-seq to discover the genome-wide sites of acetylation of lysine 56 of the histone H3 (H3K56), which is a target of three histone modifying enzymes with known roles in diabetes and insulin resistance, in human adipocytes derived from mesenchymal stem cells. Surprisingly, we find that a very large fraction of genes show some level of acetylation on H3K56, but the highest levels of acetylation are associated with genes previously reported to be involved in type 2 diabetes. Using computational methods, we propose that the transcription factor E2F4 may be involved in recruiting histone modifying enzymes to these sites. We confirm this prediction by measuring the binding of E2F4 using ChIP-seq. We also examine the binding of two other proteins using ChIP-Seq: HSF-1 and C/EBPα . HSF-1 is a master regulator of stress responses, and is a target of the same histone modifiers as H3K56. We find a high degree of overlap between HSF-1 binding and H3K56 acetylation even in cells that are not stressed. By contrast, C/EBPα , which is not known to be modified by these enzymes, shows much less overlap with the sites of H3K56 acetylation. Our results represent the first mapping of the regulatory code of human adipocytes.
Project description:The conserved Notch pathway functions in diverse developmental and disease-related processes, requiring mechanisms to ensure appropriate target-selection and gene activation in each context. To investigate, we partitioned Drosophila chromatin into different states, based on histone modifications, establishing the preferred chromatin conditions for binding of CSL, the Notch pathway transcription factor and showing that a co-operating factor, Lozenge/Runx, can help establish these conditions. While most histone modifications were unchanged by CSL binding or Notch activation, rapid changes in H3K56 acetylation occurred at Notch regulated-enhancers. This modification extended over large regions, required the histone acetyl-transferase CBP and was independent of transcription. Such rapid changes in H3K56 acetylation are a conserved indicator of enhancer activation, also occurring at mammalian Notch-regulated Hey1 and at Drosophila ecdysone-regulated genes. This core histone modification may therefore underpin the changes in chromatin accessibility needed to promote transcription following signaling activation. H3K56ac profile of control cells (KP) and of Lz overexpression cells (KL). In total 3 samples, H3K56ac ChIP in KP cells and 2 replicates of H3K56ac ChIP in KL cells.
Project description:The conserved Notch pathway functions in diverse developmental and disease-related processes, requiring mechanisms to ensure appropriate target-selection and gene activation in each context. To investigate, we partitioned Drosophila chromatin into different states, based on histone modifications, establishing the preferred chromatin conditions for binding of CSL, the Notch pathway transcription factor. While most histone modifications were unchanged by CSL binding or Notch activation, rapid changes in H3K56 acetylation occurred at Notch regulated-enhancers. This modification extended over large regions, required the histone acetyl-transferase CBP and was independent of transcription. Such rapid changes in H3K56 acetylation are a conserved indicator of enhancer activation, also occurring at mammalian Notch-regulated Hey1 and at Drosophila ecdysone-regulated genes. This core histone modification may therefore underpin the changes in chromatin accessibility needed to promote transcription following signaling activation. Su(H) profile of Kc cells transfected with GFP-Su(H). In total 6 samples, 3 replicates of anti-GFP ChIP and corresponding total input samples in Kc cells.
Project description:The conserved Notch pathway functions in diverse developmental and disease-related processes, requiring mechanisms to ensure appropriate target-selection and gene activation in each context. To investigate, we partitioned Drosophila chromatin into different states, based on histone modifications, establishing the preferred chromatin conditions for binding of CSL, the Notch pathway transcription factor. While most histone modifications were unchanged by CSL binding or Notch activation, rapid changes in H3K56 acetylation occurred at Notch regulated-enhancers. This modification required the histone acetyl-transferase CBP and was independent of transcription. Such rapid changes in H3K56 acetylation are a conserved indicator of enhancer activation, also occurring at mammalian Notch-regulated Hey1 and at Drosophila ecdysone-regulated genes. This core histone modification may therefore underpin the changes in chromatin accessibility needed to promote transcription following signaling activation. H3K56ac profile of control cells (KP) and of NICD overexpression cells (KN). In total 6 samples, with 2 input files (from 2 different conditions) and 2 replicates of H3K56ac ChIP samples of each condition.
Project description:The conserved Notch pathway functions in diverse developmental and disease-related processes, requiring mechanisms to ensure appropriate target-selection and gene activation in each context. To investigate, we partitioned Drosophila chromatin into different states, based on histone modifications, establishing the preferred chromatin conditions for binding of CSL, the Notch pathway transcription factor. While most histone modifications were unchanged by CSL binding or Notch activation, rapid changes in H3K56 acetylation occurred at Notch regulated-enhancers. This modification required the histone acetyl-transferase CBP and was independent of transcription. Such rapid changes in H3K56 acetylation are a conserved indicator of enhancer activation, also occurring at mammalian Notch-regulated Hey1 and at Drosophila ecdysone-regulated genes. This core histone modification may therefore underpin the changes in chromatin accessibility needed to promote transcription following signaling activation.
Project description:The conserved Notch pathway functions in diverse developmental and disease-related processes, requiring mechanisms to ensure appropriate target-selection and gene activation in each context. To investigate, we partitioned Drosophila chromatin into different states, based on histone modifications, establishing the preferred chromatin conditions for binding of CSL, the Notch pathway transcription factor and showing that a co-operating factor, Lozenge/Runx, can help establish these conditions. While most histone modifications were unchanged by CSL binding or Notch activation, rapid changes in H3K56 acetylation occurred at Notch regulated-enhancers. This modification extended over large regions, required the histone acetyl-transferase CBP and was independent of transcription. Such rapid changes in H3K56 acetylation are a conserved indicator of enhancer activation, also occurring at mammalian Notch-regulated Hey1 and at Drosophila ecdysone-regulated genes. This core histone modification may therefore underpin the changes in chromatin accessibility needed to promote transcription following signaling activation.
Project description:The conserved Notch pathway functions in diverse developmental and disease-related processes, requiring mechanisms to ensure appropriate target-selection and gene activation in each context. To investigate, we partitioned Drosophila chromatin into different states, based on histone modifications, establishing the preferred chromatin conditions for binding of CSL, the Notch pathway transcription factor. While most histone modifications were unchanged by CSL binding or Notch activation, rapid changes in H3K56 acetylation occurred at Notch regulated-enhancers. This modification extended over large regions, required the histone acetyl-transferase CBP and was independent of transcription. Such rapid changes in H3K56 acetylation are a conserved indicator of enhancer activation, also occurring at mammalian Notch-regulated Hey1 and at Drosophila ecdysone-regulated genes. This core histone modification may therefore underpin the changes in chromatin accessibility needed to promote transcription following signaling activation. Su(H) profile of BG3 cells in control condition and EGTA treated condition. In total 8 samples, 4 replicates of Su(H) ChIP in hbss condition and 4 replicates of Su(H) ChIP in EGTA treated BG3 cells.
Project description:The conserved Notch pathway functions in diverse developmental and disease-related processes, requiring mechanisms to ensure appropriate target-selection and gene activation in each context. To investigate, we partitioned Drosophila chromatin into different states, based on histone modifications, establishing the preferred chromatin conditions for binding of CSL, the Notch pathway transcription factor. While most histone modifications were unchanged by CSL binding or Notch activation, rapid changes in H3K56 acetylation occurred at Notch regulated-enhancers. This modification extended over large regions, required the histone acetyl-transferase CBP and was independent of transcription. Such rapid changes in H3K56 acetylation are a conserved indicator of enhancer activation, also occurring at mammalian Notch-regulated Hey1 and at Drosophila ecdysone-regulated genes. This core histone modification may therefore underpin the changes in chromatin accessibility needed to promote transcription following signaling activation. H3K56ac profile of Kc cells in control condition and EGTA treated condition. In total 4 samples, 2 replicates of H3K56ac ChIP in hbss condition and 2 replicates of H3K56ac ChIP in EGTA treated Kc cells.
Project description:The conserved Notch pathway functions in diverse developmental and disease-related processes, requiring mechanisms to ensure appropriate target-selection and gene activation in each context. To investigate, we partitioned Drosophila chromatin into different states, based on histone modifications, establishing the preferred chromatin conditions for binding of CSL, the Notch pathway transcription factor. While most histone modifications were unchanged by CSL binding or Notch activation, rapid changes in H3K56 acetylation occurred at Notch regulated-enhancers. This modification extended over large regions, required the histone acetyl-transferase CBP and was independent of transcription. Such rapid changes in H3K56 acetylation are a conserved indicator of enhancer activation, also occurring at mammalian Notch-regulated Hey1 and at Drosophila ecdysone-regulated genes. This core histone modification may therefore underpin the changes in chromatin accessibility needed to promote transcription following signaling activation. H3K56ac profile of BG3 cells in control condition and EGTA treated condition. In total 4 samples, 2 replicates of H3K56ac ChIP in hbss condition and 2 replicates of H3K56ac ChIP in EGTA treated BG3 cells.