Project description:Whole livers from HDAC6, HDAC9 deficient and wild type C57BL/6 mice, age 8-12 weeks, gender: female. Wild type mice with or without high fat diet
Project description:To investigate the role of HDAC9 in innate immnue, we measured the gene expression profile in HDAC9-knockdown macrophages in the absence of innate stimuli by gene-chip in order to find wherther HDAC9 knockdown affect the innate immune factor. We found knockdown of HDAC9 barely affected transcription of innate immnue signaling transducers. HDAC9, as a class IIa HDAC, shuttle between the nucleus and cytoplasm. Here we showed that high expression of cytoplasmic HDAC9, maybe play a Post-translational regulation role in macrophages.
Project description:Targeting histone/protein deacetylase (HDAC)-6, -9, or Sirtuin-1 (Sirt1) augments the suppressive functions of Foxp3+ T regulatory (Treg) cells, but it is unclear if this involves different mechanisms, such that combined inhibition would be beneficial. We compared the suppressive functions of Tregs from wild-type C57BL/6 mice or mice with global (HDAC6-/-, HDAC9-/-, dual HDAC6/9-/-) or conditional deletion (CD4-Cre or Foxp3-Cre and floxed Sirt1; GSE26425) alone, or after treatment with isoform-selective HDAC inhibitors (HDACi). We found the heat shock response was crucial in mediating the effects of HDAC6, but not Sirt1 inhibition. Furthermore, while HDAC6, HDAC9 and Sirt1 all deacetylate Foxp3, each has diverse effects on Foxp3 transcription, and loss of HDAC9 is associated with stabilization of Stat5 acetylation and its transcriptional activity. Targeting different HDAC can increase Treg function by multiple and additive mechanisms, indicating the therapeutic potential for combinations of HDACi in the management of autoimmunity and alloresponses post-transplant. RNA from three independent samples of magnetically separated CD4+CD25+ Treg of HDAC9-/- mice, compared to wild type (C57BL/6) control.
Project description:Muscle denervation due to injury, disease or aging results in impaired motor function. Restoring neuromuscular communication requires axonal regrowth and regeneration of neuromuscular synapses. Muscle activity inhibits neuromuscular synapse regeneration. The mechanism by which muscle activity regulates regeneration of synapses is poorly understood. Dach2 and Hdac9 are activity-regulated transcriptional co-repressors that are highly expressed in innervated muscle and suppressed following muscle denervation. Here, we report that Dach2 and Hdac9 inhibit regeneration of neuromuscular synapses. Importantly, we identified Myog and Gdf5 as muscle-specific Dach2/Hdac9-regulated genes that stimulate neuromuscular regeneration in denervated muscle. Interestingly, Gdf5 also stimulates presynaptic differentiation and inhibits branching of regenerating neurons. Finally, we found that Dach2 and Hdac9 suppress miR206 expression, a microRNA involved in enhancing neuromuscular regeneration. RNAseq on innervated and 3 day denervated adult soleus muscle from wildtype mice is compared with that from 3 day denervated soleus muscle from Dach2/Hdac9 deleted mice to identify Dach2/Hdac9-regulated genes.
Project description:E3 ubiquitin ligase E6AP and histone deacetylase HDAC6 play essential roles in the progress and development of various cancers. To explore the mechanism of E6AP and HDAC6 in liver cancer, we performed proteomic analysis with E6AP knockdown, HDAC6 knockdown and negative control HepG2 cells. We identified proteins were significantly regulated upon knockdown of E6AP or HDAC6. Pathway analysis confirmed the known phenotypic effect of E6AP and HDAC6. Overall, results from our investigation provide potential biological pathways and target genes controlled by E6AP and HDAC6 in liver cancer cells.
Project description:Histone deacetylase 9 (HDAC9) is expressed in B cells, and its overexpression has been observed in B-lymphoproliferative disorders, including B-cell non-Hodgkin lymphoma (B-NHL). We examined HDAC9 protein expression and copy number alterations in primary B-NHL samples, identifying high HDAC9 expression among various lymphoma entities and HDAC9 copy number gains in 50% of diffuse large B-cell lymphoma (DLBCL). To study the role of HDAC9 in lymphomagenesis, we generated a genetically engineered mouse (GEM) model that constitutively expressed an HDAC9 transgene throughout B-cell development under the control of the immunoglobulin heavy chain (IgH) enhancer (Eμ). Here, we report that the Eμ-HDAC9 GEM model develops splenic marginal zone lymphoma and lymphoproliferative disease (LPD) with progression towards aggressive DLBCL, with gene expression profiling supporting a germinal center cell origin, as is also seen in human B-NHL tumors. Analysis of Eμ-HDAC9 tumors suggested that HDAC9 might contribute to lymphomagenesis by altering pathways involved in growth and survival, as well as modulating BCL6 activity and p53 tumor suppressor function. Epigenetic modifications play an important role in the germinal center response, and deregulation of the B-cell epigenome as a consequence of mutations and other genomic aberrations are being increasingly recognized as important steps in the pathogenesis of a variety of B-cell lymphomas. A thorough mechanistic understanding of these alterations will inform the use of targeted therapies for these malignancies. These findings strongly suggest a role for HDAC9 in B-NHL and establish a novel GEM model for the study of lymphomagenesis and, potentially, preclinical testing of therapeutic approaches based on histone deacetylase inhibitors.
Project description:To investigate the specific roles of HDAC6 in the development of liver cancer, we employed large-scale gene expression analysis to identify the molecular signature that may affect enabling characteristics of cancer cells. Differentially expressed genes were analyzed on the Hep3B cells transfected with empty mock or pcDNA_HDAC6, and recapitulated molecular signatures that related to hallmarks of cancer. To characterize the biological effects of HDAC6 on liver cancer, large-scale gene expression analysis to identify molecular signature was performed on the Hep3B cells.
Project description:In the present study, we investigated the importance of histone deacetylase 6 (HDAC6) for glucocorticoid receptor (GR) mediated effects on glucose metabolism, and its potential as a therapeutic target for the prevention of glucocorticoid (GC)-induced diabetes. Dexamethasone (dex)-induced hepatic glucose output and GR translocation were analysed in wildtype (wt) and HDAC6-deficient (HDAC6ko) mice. The effect of the specific HDAC6-inhibitor tubacin was analysed in-vitro. Wt and HDAC6ko mice were subjected to 3 weeks dex treatment before analysis of glucose and insulin tolerance. HDAC6ko mice showed impaired dex-induced hepatic GR translocation. Accordingly, dex induced expression of a large number of hepatic genes was significantly attenuated in mice lacking HDAC6 and by tubacin in-vitro. Glucose output of primary hepatocytes from HDAC6ko mice was diminished. A significant improvement of dex-induced whole-body glucose intolerance as well as insulin resistance in HDAC6ko mice compared to wt littermates was observed. The present study demonstrates that HDAC6 is an essential regulator of hepatic GC stimulated gluconeogenesis and impairment of whole body glucose metabolism through modification of GR nuclear translocation. Selective pharmacological inhibition of HDAC6 may provide a future therapeutic option against the pro-diabetogenic actions of GCs. In this dataset, we include the expression data obtained from isolated RNA of dissected mouse livers using wildtype and HDAC6 deficient animals which were treated over a timespan of 3 weeks with 1mg/kg dexamethasone and vehicle respectively. These data are used to show the hdac6-deficiency mediated attenuation of several dexamethasone induced genes. 12 samples in total were analyzed. 3 samples of different animals of each group (wt vehicle, wt dexamethasone, hdac6ko vehicle and hdac6ko dexamethasone)
Project description:The Tip60 (also known as Kat5) lysine acetyltransferase functions broadly as a transcriptional co-activator that acetylates histones. In contrast, Tip60 functions in embryonic stem cells (ESCs) both to silence genes that promote differentiation and to activate genes required for proliferation. The mechanism by which Tip60 functions as a repressor is unknown. Here we show that the class II histone deacetylase Hdac6 co-purifies with Tip60-p400 complex from ESCs and is necessary for complete silencing of most differentiation genes targeted by Tip60. In contrast to differentiated cells, where Hdac6 is mainly cytoplasmic and does not interact with Tip60, Hdac6 is largely nuclear in ESCs and neural stem cells (NSCs) and interacts with Tip60-p400 in both cell types. Hdac6 is enriched at promoters bound by Tip60-p400 in ESCs, but while Tip60 binds on both sides of transcription start sites (TSSs), Hdac6 binding overlaps with only the downstream Tip60 peak. Surprisingly, Hdac6 does not deacetylate histones at these sites, but rather is required for Tip60 binding. These data suggest that nuclear exclusion of Hdac6 during differentiation plays a major role in modulation of Tip60-p400 function. We determined the genome-wide localization of Tip60 and Hdac6 in mouse ES cells, and examined genomic binding profiles of Tip60 and Hdac6 upon indicated knockdown by ChIP-seq. We examined genomic binding profiles of p400 upon indicated knockdown by ChIP-seq.
Project description:In order to study the role of the HDAC9 in human mesenchymal stem cell differentiation, gene expression analysis was performed with inducible silencing of HDAC9 in human mesenchymal stem cell purchasing from Cyagen Biosciences (HUXMA-90011, Guangzhou, China). Transcriptomic analysis performed on mRNA of human mesenchymal stem cells transfected with lentiviral knockdown HDAC9 (lenti-HDAC9) particles revealed down and up regulation of transcripts of hMSCs differentiation genes