The role of histone H2Az in cardiac gene expression

组蛋白 H2Az 在心脏基因表达中的作用

• 批准号: 7095354
• 负责人: Maha Abdellatif
• 金额: $ 38.88万
• 依托单位: UNIV OF MED/DENT OF NJ-NJ MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-01 至 2010-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7095354
• 关键词: RNA interference; biotechnology; cardiac myocytes; cell growth regulation; chromatin immunoprecipitation; developmental genetics; disease /disorder model; functional /structural genomics; gene expression; genetic regulation; genetic transcription; genetically modified animals; heart enlargement; histones; laboratory mouse; laboratory rat; newborn animals; nucleosomes; protein isoforms; protein structure function; site directed mutagenesis; subtraction hybridization; tissue /cell culture; yeast two hybrid system

DESCRIPTION (provided by applicant): Changes in the gene expression profile of a cell, underlie changes in its phenotype, in response to a broad range of physiological or pathological stimuli. This process is very tightly regulated at multiple levels, from the membrane to the nucleus. Many of the upstream signaling pathways and second messengers that regulate the transcriptional machinery continue to be heavily investigated. The end result does not only include modification of transcription factors, but in addition, remodeling, post-translational alterations, and/or variant replacements of histones. While the main role of histones is architectural, involving chromatin packaging, it is becoming increasingly evident that it also plays an interactive role in regulating gene transcription. The mechanisms involved, though, remain poorly understood in mammalian cells in general or in cardiac myocytes in particular. We have previously reported that a specific isoform of histone H2A, termed H2Az, is upregulated during cardiac hypertrophy. Our preliminary results show that in the neonatal mouse this histone is expressed at relatively high levels in all organs but drop to undetectable amounts in the normal adult heart and skeletal muscle only. The functions of H2Az are essential for development, non-redundant, and highly conserved, the mechanisms of which remain to be investigated in mammalian cells. In lower eukaryotes though, it has been specifically implicated in nucleosomal remodeling and transcriptional activation. This proposal will investigate its role in the heart during cardiac hypertrophy. Built on our preliminary results, we hypothesize that H2Az is necessary for hypertrophic growth through directly regulating the expression of a subset of growth-related genes. The specific aims of this grant are: 1. To determine the role and mechanism of function of H2Az in cardiac hypertrophy, using mutagenesis and RNA interference. 2. To identify genes that are regulated by H2Az, using chromatin immunoprecipitation (ChIP) and subtractive hybridization. 3. To identify H2Az regulatory/effector proteins and their functions, using the yeast two-hybrid system. 4. Characterize a transgenic mouse model over-expressing H2Az in the heart.

描述（申请人提供）：响应广泛的生理或病理刺激，其表型的基因表达谱的变化，其表型的基础变化。从膜到核的多个水平都非常严格地调节。许多调节转录机械的上游信号通路和第二个使者继续进行大量研究。最终结果不仅包括转录因子的修改，而且还包括组蛋白的重塑，翻译后变化和/或变体替代品。尽管组蛋白的主要作用是涉及染色质包装的建筑，但越来越明显的是，它在调节基因转录中也起着互动作用。但是，所涉及的机制在通常的哺乳动物细胞中，尤其是心肌细胞中的理解较低。我们先前已经报道说，在心脏肥大期间，组蛋白H2A的特异性同工型被上调。我们的初步结果表明，在新生小鼠中，该组蛋白在所有器官中均以相对较高的水平表达，但仅在正常成人心脏和骨骼肌中降低至无法检测的量。 H2AZ的功能对于发育，非冗余和高度保守至关重要，其机制在哺乳动物细胞中仍有待研究。但是，在较低的真核生物中，它已特别与核小体的重塑和转录激活有关。该建议将调查其在心脏肥大期间其在心脏中的作用。基于我们的初步结果，我们假设H2AZ是通过直接调节与生长相关基因的一部分表达的表达所必需的。该赠款的具体目的是：1。使用诱变和RNA干扰确定H2AZ在心脏肥大中的作用和机理。 2。使用染色质免疫沉淀（CHIP）和减法杂交鉴定受H2AZ调节的基因。 3。使用酵母双杂交系统鉴定H2AZ调节/效应蛋白及其功能。 4。表征心脏中过表达H2AZ的转基因小鼠模型。