The Role of HDAC3 in Cardiac Growth and Development

HDAC3 在心脏生长和发育中的作用

• 批准号: 7143835
• 负责人: Lazaros K. Kochilas
• 金额: $ 7.5万
• 依托单位: RHODE ISLAND HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7143835
• 关键词: amidohydrolases; antisense nucleic acid; cardiac myocytes; cardiogenesis; cell differentiation; cell sorting; cell transplantation; congenital heart disorder; fluorescence microscopy; genetically modified animals; heart function; immunofluorescence technique; mutant; nonmammalian vertebrate embryology; zebrafish

DESCRIPTION (provided by applicant): The process of cardiac development incorporates cell differentiation and proliferation, which lead to the formation of the mature heart. Abnormalities in cardiac development result in congenital heart diseases, which is the most frequent form of birth defects in humans. More specifically, disruption of pathways affecting cardiac growth could be the underlying etiology in a subset of children born with hypoplastic left or right heart. Understanding the myocardial-specific molecular mechanisms by which signaling pathways control proliferation during cardiogenesis is a central issue in cardiac development and disease. These pathways are complex, and in many cases implicate transcription factors and cell cycle regulators. Covalent chromatin modifications play a critical role in transcriptional regulation and cell cycle progression, and therefore are expected to affect theses processes in the heart as well. Of these modifications, acetylation by histone acetyltransferases (HATs) and its reversal by histone deacetylases (HDACs) have been most studied and appreciated as a key event in regulating these processes. Experimental data from the mouse and zebrafish models suggest that HDAC1, a class I HDAC family member, plays an important role in embryonic cardiac growth and development. However, the role of other class I HDACs in cardiac growth and development remains unknown. As an extension of the principal investigator's interest in embryonic myocardial growth and development, he initiated a comprehensive analysis of the role of class I HDACs other than HDAC1. Preliminary studies suggest an important role for HDAC3, a class I member, both in cardiac growth and in development. In this pilot study, the investigators propose experiments that will offer insights into the role of HDAC3 in embryonic cardiac growth and development. They will pursue two aims: Specific Aim 1 will determine the effect of hdac3 deficiency in the zebrafish embryonic heart. The investigators will address this question by generating hdac3-deficient zebrafish embryos by disrupting hdac3 function with morpholino antisense oligonucleotides and comparing them with hdac3 mutants. The hdac3 deficient embryos will be evaluated by morphological and functional analysis with particular emphasis on the heart. Heart characterization will be completed by assessment of differentiation by the use of molecular markers, cell count determination, apoptosis, and proliferation assays. Specific Aim 2 will determine what are the cardiac defects in the hdac3 deficient embryos due to the loss of hdac3 function within cardiomyocytes or due to effects upon cellular functions in other support tissues? The investigators will address this question by reciprocal cell transplantations between control and hdac3-deficient embryos. They will also use selected molecular markers to dissect extracardiac processes relevant to cardiac development that are potentially affected in the hdac3 deficient embryos.

描述（由申请人提供）：心脏发育的过程融合了细胞分化和增殖，从而导致成熟心脏的形成。 心脏发育的异常导致先天性心脏病，这是人类最常见的先天缺陷形式。 更具体地说，影响心脏生长的途径的破坏可能是患有左或右心脏发育不良的儿童的基本病因。 了解心肌特异性分子机制，信号通路在心脏病发生过程中控制增殖是心脏发育和疾病的核心问题。 这些途径很复杂，在许多情况下，这些途径暗示转录因子和细胞周期调节剂。 共价染色质修饰在转录调控和细胞周期进程中起关键作用，因此有望影响心脏中的这些过程。 在这些修饰中，组蛋白乙酰转移酶（HATS）及其由组蛋白脱乙酰基酶（HDACS）逆转的乙酰化已被最多研究，并且是调节这些过程的关键事件。 来自小鼠和斑马鱼模型的实验数据表明，I类HDAC家族成员HDAC1在胚胎心脏生长和发育中起着重要作用。 但是，其他I类HDAC在心脏增长和发育中的作用仍然未知。 作为主要研究者对胚胎心肌生长和发育的兴趣的扩展，他对HDAC1以外的I类作用进行了全面分析。 初步研究表明，在心脏增长和发育中，I类成员HDAC3的重要作用。 在这项试点研究中，研究人员提出了实验，将为HDAC3在胚胎心脏增长和发育中的作用提供见解。 他们将追求两个目标：特定目标1将确定HDAC3缺乏症对斑马鱼胚胎心脏的影响。 研究人员将通过用morpholino反义寡核苷酸破坏HDAC3功能并将其与HDAC3突变体进行比较，从而通过产生HDAC3缺陷斑马鱼胚胎来解决这个问题。 HDAC3缺乏胚胎将通过形态学和功能分析评估，并特别强调心脏。 通过使用分子标记，细胞计数测定，凋亡和增殖测定法评估分化的评估，将完成心脏特征。 特定的目标2将确定由于心肌细胞中HDAC3功能的丧失或其他支撑组织中细胞功能的影响，HDAC3缺陷胚胎中的心脏缺陷是什么？ 研究人员将通过对照和HDAC3缺陷胚胎之间的相互细胞移植来解决这个问题。 他们还将使用选定的分子标记物来剖析与心脏发育相关的心外过程，这些过程可能受到HDAC3缺乏胚胎的影响。