Project description:In this study, we analyzed inflammatory response to Poly:IC under HDAC8 or HDAC9 silencing keratinocyte and performed pathway analysis by RNA-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
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:HDAC8 expression is causative for resistance to BRAF inhibiton and increased migration in BRAF mutant melanoma cell lines. Changes in gene expression were determined upon forced HDAC8 expression in an isogenic cell line.
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: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:Patients with heterozygous missense mutations in the ACTA2 or MYH11 genes are known to exhibit thoracic aortic aneurysm (TAA) and a risk of early onset aortic dissection. However, less common phenotypes involving arterial obstruction are also observed, including coronary and cerebrovascular stenotic disease. Recently an epigenetic complex containing the histone deacetylase HDAC9 and the long noncoding RNA, MALAT1 was implicated in pathologic vascular smooth muscle cell phenotypic changes in aneurysmal disease, however its involvement in stenotic disease has not been explored. Herein we implicate the HDAC9-MALAT1 complex in transcriptional silencing of contractile associated gene products, known to undergo downregulation in stenotic lesions. Furthermore, neointimal formation was inhibited in Hdac9 or Malat1 deficient mice with preservation of contractile protein expression. Pharmacologic targeting of the complex through either MALAT1 antisense oligonucleotides or inhibition of the methyltransferase EZH2 reduced neointimal formation. In conclusion, we report the implication of the HDAC9-MALAT1 complex in stenotic disease and demonstrate that pharmacologic therapy based on epigenetic targets can ameliorate arterial obstruction in an experimental system.
Project description:HDAC8, a member of class I HDACs, plays a pivotal role in cell cycle regulation by deacetylating the cohesin subunit SMC3. While cyclins and CDKs are well-established cell cycle regulators, our knowledge of other regulators remains limited. Here we reveal acetylated K202 in HDAC8 as a key cell cycle regulator responsive to stress. K202 acetylation in HDAC8, primarily catalyzed by Tip60, negatively modulates HDAC8 activity, leading to increased SMC3 acetylation and cell cycle arrest. Furthermore, cells mimicking K202 acetylation display significant alterations in gene expression, potentially linked to changes in 3D genome structure, including enhanced chromatid loop interactions. K202 acetylation negatively impacts cell cycle progression by disrupting the expression of cell cycle-related genes and sister chromatid cohesion, resulting in G2/M phase arrest. These findings illuminate the reversible acetylation of HDAC8 as a novel cell cycle regulator, expanding our understanding of stress-responsive cell cycle dynamics.
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.