Project description:Aberrations in chromatin dynamics play a fundamental role in tumorigenesis, yet relatively little is known of the molecular mechanisms linking histone lysine methylation to neoplastic disease. ING4 (Inhibitor of Growth 4) is a native subunit of an HBO1 histone acetyltransferase (HAT) complex and a tumor suppressor protein. Here we show a critical role for the specific read-out of histone H3 trimethylated at lysine 4 (H3K4me3) by the ING4 PHD finger in mediating ING4 gene expression and tumor suppressor functions. The interaction between ING4 and H3K4me3 augments the acetylation activity of HBO1 on H3 tails, and drives H3 acetylation at ING4 target promoters to effect a DNA damage-dependent gene expression program. Further, ING4 facilitates apoptosis in response to genotoxic stress and inhibits anchorage-independent cell growth, and these functions are dependent on ING4 interactions with H3K4me3. Together, our results demonstrate a mechanism for brokering crosstalk between H3K4 methylation and histone H3 acetylation, and reveal a new molecular link between chromatin modulation and tumor suppressor mechanisms. ING4 ChIP-chip +/- Doxorubicin treatment in HT1080 cells on Nimblegen whole genome promoter array 4 samples: HT1080 cell lines stably expressing Flag-ING4 or Flag-ING4-D213A, +/- doxorubicin
Project description:Aberrations in chromatin dynamics play a fundamental role in tumorigenesis, yet relatively little is known of the molecular mechanisms linking histone lysine methylation to neoplastic disease. ING4 (Inhibitor of Growth 4) is a native subunit of an HBO1 histone acetyltransferase (HAT) complex and a tumor suppressor protein. Here we show a critical role for the specific read-out of histone H3 trimethylated at lysine 4 (H3K4me3) by the ING4 PHD finger in mediating ING4 gene expression and tumor suppressor functions. The interaction between ING4 and H3K4me3 augments the acetylation activity of HBO1 on H3 tails, and drives H3 acetylation at ING4 target promoters to effect a DNA damage-dependent gene expression program. Further, ING4 facilitates apoptosis in response to genotoxic stress and inhibits anchorage-independent cell growth, and these functions are dependent on ING4 interactions with H3K4me3. Together, our results demonstrate a mechanism for brokering crosstalk between H3K4 methylation and histone H3 acetylation, and reveal a new molecular link between chromatin modulation and tumor suppressor mechanisms.
Project description:Inhibitor of growth 4 and 5 (ING4 and ING5) are chromatin-binding proteins in the KAT6A, KAT6B and KAT7 histone acetyltransferase protein complexes. Heterozygous mutations in the KAT6A or KAT6B gene cause human disorders with cardiac defects, but the contribution of their chromatin adaptor proteins to development is unknown. We found that Ing5–/– mice had isolated cardiac ventricular septal defects. ING4 and ING5 are structurally similar proteins, suggesting a degree of redundancy. Combined loss of ING4 and ING5 caused developmental arrest at embryonic day E8.5, loss of histone H3 lysine 14 acetylation (H3K14ac), a reduction in H3K23ac levels and disruption of developmental gene expression in Ing4–/–Ing5–/– compared to control embryos. E12.5 Ing4+/–Ing5–/– hearts showed a paucity of epicardial cells and epicardium-derived cells, failure of myocardium compaction and coronary vasculature defects, accompanied by a reduction in the expression of epicardium genes compared to control hearts. In addition, a reduction in the expression of genes required for cell adhesion, both in whole E8.75 Ing4–/–Ing5–/– embryos and in E10.5 Ing4+/–Ing5–/– hearts compared to controls was observed. In vitro assessment of fibroblast and proepicardium explants revealed cell spreading and outgrowth defects. Our findings suggest that ING4 and ING5 are essential for heart development and promote epicardium and epicardium-derived cell fates and mutation of the human ING5 gene as a possible cause of isolated ventricular septal defects.
Project description:DNase-seq on 25 year old human male hematopoietic multipotent progenitor cell For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODE_Data_Use_Policy_for_External_Users_03-07-14.pdf
Project description:DNase-seq on 25 year old human adult male hematopoietic multipotent progenitor cell line For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODE_Data_Use_Policy_for_External_Users_03-07-14.pdf
Project description:DNase-seq on 25 year old human adult male hematopoietic multipotent progenitor cell line For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODE_Data_Use_Policy_for_External_Users_03-07-14.pdf
Project description:Inhibitor of growth 4 and 5 (ING4 and ING5) are chromatin-binding proteins in the KAT6A, KAT6B and KAT7 histone acetyltransferase protein complexes. Heterozygous mutations in the KAT6A or KAT6B gene cause human disorders with cardiac defects, but the contribution of their chromatin adaptor proteins to development is unknown. We found that Ing5-/- mice had isolated cardiac ventricular septal defects. ING4 and ING5 are structurally similar proteins, suggesting a degree of redundancy. Combined loss of ING4 and ING5 caused developmental arrest at embryonic day E8.5, loss of histone H3 lysine 14 acetylation (H3K14ac) and a reduction in H3K23ac levels. Ing4+/-Ing5-/- hearts showed a paucity of epicardial cells and epicardium-derived cells, failure of myocardium compaction and coronary vasculature defects, accompanied by a reduction in the expression of epicardium genes. Our findings suggest that ING4 and ING5 are essential for heart development and promote epicardium and epicardium-derived cell fates and mutation of the human ING5 gene as a possible cause of isolated ventricular septal defects.