Genetics and Structure of Trabecular Myocardium in Development and Disease

 描述(由申请人提供)：本提案描述了一项为期五年的有指导的职业发展计划，旨在为Rima Arnaout博士成为一名独立调查员的长期职业目标做好准备。这项建议建立在阿诺特博士作为心脏病学家和心血管发展基础科学家的背景之上，通过提供生物信息学方法、基因组分析方法以及对研究方法的成功至关重要的其他技术方面的培训。加州大学旧金山分校心血管研究所所长、心血管研究专家肖恩·考夫林博士将担任该项目的主要导师。考夫林博士的指导是一项培训计划的一部分，该计划包括由心血管疾病发展领域的领导者组成的咨询委员会的正式指导、正式的课程和技能培训，以及一项将提供发育生物学和遗传学方面的严格培训的研究计划。这项工作将在一个出色的心血管研究环境中得到支持，该环境具有培养独立内科科学家所需的智力和方案支持及基础设施。在前期工作中，阿诺特博士创造了一些工具，可以用来研究心室肌增厚和重塑形成小梁的过程。小梁形成是心脏正常发育和功能过程中必不可少的过程，一些先天性和遗传性心脏病的特点是小梁减少或过多。因此，这些研究的总体目标是阐明在发育和再生过程中骨小梁形成的启动机制。这一目标将通过开发斑马鱼模型系统的特定优势并使用利钠肽A(NPPA)作为标记和操纵小梁心肌的工具来实现。阿纳奥特博士将首先通过对斑马鱼进行基因敲除和表达研究，检验NPPA参与发育过程中小梁形成的启动这一假设。为了研究心内膜-心肌接触在体内小梁形成中的作用，阿纳奥特博士将使用跨突触伙伴的GFP重建系统(GRASH)。然后，她将检验这一假设，即当小梁受到选择性损伤时，成年斑马鱼心脏的再生生长来自NPPA阳性细胞。与以前的心脏损伤模型相比，阿诺特博士的心脏损伤模型更接近于最常见的一种人类心脏损伤。最后，Arneout博士将扩展她对小梁心肌和非小梁心肌的分析，使用RNA-Seq来比较基线和再生时小梁心肌中的基因程序，并发现新的基因和途径，以在脊椎动物系统中进行研究。通过确定在发育中和心脏损伤后小梁形成的启动和维持的机制，本工作将为几种先天性心脏病的发病机制提供有价值的见解，并为掌握损伤后的心脏再生奠定重要基础。

 DESCRIPTION (provided by applicant): This proposal describes a five-year mentored career development program designed to prepare Dr. Rima Arnaout for her long-term career goal to be an independent investigator. This proposal builds upon Dr. Arnaout's background as a cardiologist and a basic scientist in cardiovascular development by providing training in bioinformatics approaches to genome analysis as well as other techniques critical to success of the research approach. Dr. Shaun Coughlin, Director of the Cardiovascular Research Institute at the University of California, San Francisco and an expert in cardiovascular research, will serve as the primary mentor for this project. Dr. Coughlin's mentorship is part of a training plan that includes formal mentorship by an advisory committee of leaders in cardiovascular development, formal coursework and skills training, and a research plan that will provide rigorous training in developmental biology and genetics. This work will be supported in an outstanding environment for cardiovascular research rich with the intellectual and programmatic support and infrastructure necessary for the development of an independent physician-scientist. In preliminary work, Dr. Arnaout has created tools that can be used to study the thickening and remodeling of the ventricular myocardium to form trabeculae. Trabeculation is an essential process in normal heart development and function, and several congenital and heritable heart diseases are characterized by hypo- or hyper- trabeculation. The overall goal of the studies proposed is therefore to illuminate the mechanisms governing initiation of trabeculation in development and regeneration. This goal will be achieved by exploiting specific strengths of the zebrafish model systems and by using natriuretic peptide A (nppa) as a tool to mark and manipulate trabeculated myocardium. Dr. Arnaout will first test the hypothesis that nppa participates in the initiation of trabeculation during development by performing knockout and expression studies in zebrafish. To interrogate roles of endocardial-myocardial contact in trabeculation in vivo, Dr. Arnaout will use the GFP Reconstitution Across Synaptic Partners (GRASP) system. She will then test the hypothesis that the regenerative growth in adult zebrafish hearts arises from nppa-positive cells when trabeculae are selectively injured. Compared to prior models for heart injury, Dr. Arnaout's model for heart injury more closely approximates the most common kind of human heart injury. Finally, Dr. Arnaout will extend her analysis of trabeculated vs non-trabeculated myocardium, using RNA-Seq to compare gene programs in trabecular myocardium at baseline and in regeneration and discover novel genes and pathways to investigate across vertebrate systems. By identifying the mechanisms responsible for the initiation and maintenance of trabeculation in development and after heart injury, the work proposed will provide valuable insight into the pathogenesis of several congenital heart diseases and also lay important groundwork for mastering cardiac regeneration after injury.