Characterizing the RNA-mediated recruitment of histone deacetylases to chromatin

表征 RNA 介导的组蛋白脱乙酰酶向染色质的募集

• 批准号: 10680276
• 负责人: James Kang Guo
• 金额: $ 5.27万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2028-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10680276
• 关键词: Affinity Chromatography; Antisense RNA; Binding; Binding Proteins; Binding Sites; Cancerous; Cell Cycle; Cell Nucleus; Cells; Chromatin; Complex; DNA Binding; DNA-Binding Proteins; Data; Enzymes; Future; Gene Expression; Gene Expression Regulation; Gene Silencing; Gene Targeting; Genes; Genetic; Genome; Guide RNA; HDAC1 gene; HDAC3 gene; Health; Histone Deacetylase; Histone Deacetylase Inhibitor; Histone Deacetylation; Human; Immunoprecipitation; Knock-out; Link; Malignant Neoplasms; Mass Spectrum Analysis; Measures; Mediating; Methods; Mission; Molecular; Multiprotein Complexes; Mutate; Nuclear; Pathology; Patients; Pharmaceutical Preparations; Protein Isoforms; Proteins; RNA; RNA Binding; RNA-Binding Proteins; Repression; Research; Research Project Grants; Role; Site; Specificity; Suppressor-Effector T-Lymphocytes; Testing; Therapeutic; Time; Toxic effect; Tumor Suppressor Genes; United States National Institutes of Health; Untranslated RNA; Work; X Chromosome; cancer therapy; cancer type; chromatin modification; crosslink; effective therapy; experimental study; gene repression; genetic manipulation; genetic regulatory protein; genomic locus; improved; in vivo; inhibitor; link protein; mRNA Precursor; novel; pharmacologic; protein complex; public database; recruit; side effect; therapeutic target; transcription factor; tumor

PROJECT SUMMARY Global histone deacetylation is linked to many types of cancer and is controlled by histone deacetylases (HDACs). Although HDAC inhibitors are widely used in cancer treatment, their activity does not target specific HDAC isoforms nor specific genes and therefore results in significant side effects for patients. Thus, there is a pressing need to target HDAC activity in a highly precise, gene-specific manner to develop safer and more effective treatments. The overall objective of this proposal is to understand how HDACs are recruited to specific genome regions. Because HDACs do not possess intrinsic DNA binding activity, they are thought to be recruited to chromatin through interactions with DNA binding proteins, though this mechanism has not been fully explored. Recently, our lab and others identified that the SHARP RNA-binding protein directly interacts with the Xist long noncoding RNA (lncRNA) to specifically recruit HDAC3 to the future inactive X chromosome (Xi). In this way, the Xist-SHARP/SMRT/HDAC3 repressive complex deacetylates histones and silences gene expression on the Xi. Our lab has also demonstrated that SHARP localizes to many nuclear sites (beyond the Xi) in an RNA-dependent manner, raising the question of which additional RNAs recruit it (along with HDAC3) and to what specific genomic locations. Notably, nearly all human HDACs associate within multi-protein complexes containing SHARP and other RNA-binding proteins, suggesting that this mechanism of RNA-guidance may extend beyond SHARP and Xist. I hypothesize that HDAC complexes are recruited by RNAs to achieve specificity to their various regulatory targets throughout the nucleus. First, I will determine which SHARP-RNA interactions are functionally important by genetically perturbing the SHARP binding sites of candidate RNAs. I will then measure effects on gene expression and if HDAC3 activity is required for these effects (Aim 1). Second, I will comprehensively identify RNA-binding proteins associated with other cancer-associated HDACs and define their in vivo RNA binding sites. I will then determine which protein-bound candidate RNAs from this screen are regulated in an HDAC-dependent manner (Aim 2). The proposed research has the potential to transform our understanding of RNAs and RNA- binding proteins as central regulators in organizing chromatin modifications by HDACs in both normal and cancerous cell states.

项目总结