Identification of histone modifications in cardiomyocytes of conditional HDAC4 knockout mice
Ontology highlight
ABSTRACT: Histone Deacetylase 4 (HDAC4) is known to contribute to cardiac remodeling processes. We wanted to identify and compare different genome wide targets of HDAC4 to well described interaction partners and its functional consequences. Therefore, we used a model of adult cardiomyocytes isolated from HDAC4 knockout mice and Wildtyp (WT) controls. We looked for HDAC4s contribution to changes of activating histone modifications (H3K4me3, H3K9ac, H3K27ac) and repressive pendants (H3K9me2 and H3K27me3).
Project description:To identify direct CaMKII-dependent downstream genes of H3S28p we used chromatin-immunoprecipitation followed by massive parallel DNA sequencing (ChIPseq) analysis of isolated adult murine cardiomyocytes from CamKII WT as well as from CaMKIIγ/CaMKIIδ double knockout (DKO) . DKO and WT cells were subjected to long-term Iso treatment for 24 h to maximize CaMKII-dependent H3S28p.
Project description:The experiment was designed to assess genome-wide binding sites of Myocyte Enhancer Factor 2 (MEF2) in adult mouse ventricular cardiomyocytes.
Project description:Myocyte enhancer factor 2 contributes as a transcription factor to cardiac remodeling processes. We wanted to link and compare known myocyte enhancer factor 2 targets to overall targets. Therefore, we used a model of neonatal rat cardiomyocytes and precipitated sheared chromatin samples with 5µg of MEF2 Ab.
Project description:Access to DNA is the first level of control in regulating gene transcription, a control that is also critical for maintaining DNA integrity. Cellular senescence is characterized by profound transcriptional rearrangements and accumulation of DNA lesions. Here, we discovered an epigenetic complex between HDAC4 and HDAC1/HDAC2 that is involved in the erase of H2BK120 acetylation. The HDAC4/HDAC1/HDAC2 complex modulates the efficiency of DNA repair by homologous recombination, through dynamic deacetylation of H2BK120. Deficiency of HDAC4 leads to accumulation of H2BK120ac, impaired recruitment of BRCA1 and CtIP to the site of lesions, accumulation of damaged DNA and senescence. In senescent cells this complex is disassembled because of increased proteasomal degradation of HDAC4. Forced expression of HDAC4 during RAS-induced senescence reduces the genomic spread of γH2AX and affects H2BK120ac levels, which are increased in DNA-damaged regions accumulated during RAS-induced senescence. In summary, degradation of HDAC4 during senescence causes the accumulation of damaged DNA and contributes to the activation of the transcriptional program controlled by super-enhancers that maintains senescence.
Project description:Hdac4 has been found to modulate symptoms in Huntington's Disease (HD) mouse models through an uknown mechanism unrelated to any enzymatic activity. We investigated the protein-protein interactions to gain insight into the role of Hdac4 in HD.
Project description:Transcriptional alterations are characteristic of persistent pain states but the key regulators remain elusive. Using a conditional knockout (cKO) strategy in mice we sought to determine whether loss of the transcriptional co-repressor histone deacetylase four (HDAC4) would have implications for sensory neuron transcription and nociception. HDAC4 was found to be largely dispensable for transcriptional regulation of naïve sensory neurons but was required for transcriptional responses after injury, with Calca and Trpv1 expression consistently downregulated in HDAC4 cKO compared to littermate controls (0.2-0.44 fold). This downregulation corresponded to reduced sensitivity to capsaicin in vitro (76% +/- 4.4% wildtype capsaicin responders vs 56.9% +/- 4.7% cKO responders) and to reduced thermal hypersensitivity in the complete Freund’s adjuvant model of inflammatory pain (1.3-1.4 fold improvement). These data indicate that HDAC4 is a novel inflammatory pain mediator and may be a good therapeutic target, capable of orchestrating the regulation of multiple downstream effectors. Total RNA was extracted from HDAC4 cKO and HDAC4 fl/fl naïve adult lumbar dorsal root ganglia (n=3/group). mRNA expression was compared using Affymetrix Mouse Gene Arrays (Mouse Gene 2.0ST) run on a GeneChip Fluidics Station 450. Chips were scanned on an Affymetrix GeneChip Scanner.
Project description:To identify whether Hdac4/5 were enriched in MuERVL directly, we performed Hdac4/5 ChIP-seq with anti-Hdac4/5 antibody in wildtype ESCs. we conclude that Hdac4/5 binding were enriched on MuERVL-int region and weakly enriched on MT2, suggesting a direct regulatory role of Hdac4/5 on MuERVL expression.
Project description:To explore the downstream genes of HDAC4, we performed RNA-seq to screen after knocking down HDAC4 in 5-8F cells, a nasopharyngeal carcinoma cell line.
Project description:Transcription factor Ebf1 is an important determinant of early B lymphopoiesis. To gain insight into differentiation stage-specific functions of Ebf1, we conditionally inactivated Ebf1. We found that Ebf1 is required for proliferation, survival and signaling of pro-B cells and peripheral B cell subsets. The proliferation defect of Ebf1-deficient pro-B cells, including the impaired expression of IL-7Ra and several cell cycle regulators, is overcome by transformation with v-Abl. The survival defect of transformed Ebf1fl/fl pro-B cells can be rescued by the forced expression of the Ebf1 targets c-Myb or Bcl-xL. In mature B cells, Ebf1 deficiency interferes with the BAFF-R and BCR-dependent Akt signaling pathways, as well as with germinal center formation and class switch recombination. Genome-wide analyses of Ebf1 binding and Ebf1-mediated gene expression in mature B cells and comparison with reported data sets in pro-B cells provide insight into the basis for lineage- and stage-specific functions of Ebf1. EBF1 binding in splenic B cells in mice