Genetics and Structure of Trabecular Myocardium in Development and Disease

 描述（由申请人提供）：本提案描述了一个为期五年的指导职业发展计划，旨在为Rima Arnaout博士的长期职业目标做好准备，成为一名独立的研究者。该提案建立在Arnaout博士作为心脏病专家和心血管发育基础科学家的背景之上，通过提供基因组分析的生物信息学方法以及对研究方法成功至关重要的其他技术方面的培训。弗朗西斯科加州大学心血管研究所所长、心血管研究专家Shaun Coughlin博士将担任该项目的主要导师。Coughlin博士的指导是培训计划的一部分，该计划包括由心血管发育领导者咨询委员会提供的正式指导，正式的课程和技能培训，以及将提供发育生物学和遗传学严格培训的研究计划。这项工作将在心血管研究的优秀环境中得到支持，该环境具有独立医生-科学家发展所需的智力和计划支持以及基础设施。在初步工作中，Arnaout博士已经创建了可用于研究心室心肌增厚和重塑以形成小梁的工具。小梁形成是正常心脏发育和功能的重要过程，一些先天性和遗传性心脏病的特征是小梁形成不足或过度。因此，提出的研究的总体目标是阐明小梁形成在发育和再生中的启动机制。这一目标将通过利用斑马鱼模型系统的特定优势和使用利钠肽A（nppa）作为标记和操纵小梁化心肌的工具来实现。Arnaout博士将首先通过在斑马鱼中进行敲除和表达研究来检验nppa参与发育过程中小梁形成起始的假设。为了研究心内膜-心肌接触在体内小梁形成中的作用，Arnaout博士将使用GFP跨突触伙伴重建（GRASP）系统。然后，她将检验这样一个假设，即当骨小梁被选择性损伤时，成年斑马鱼心脏的再生生长来自nppa阳性细胞。与先前的心脏损伤模型相比，Arnaout博士的心脏损伤模型更接近于最常见的人类心脏损伤。最后，Arnaout博士将扩展她对小梁化与非小梁化心肌的分析，使用RNA-Seq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来研究脊椎动物系统。通过确定在发育过程中和心脏损伤后小梁形成的启动和维持机制，所提出的工作将为了解几种先天性心脏病的发病机制提供有价值的见解，也为掌握心脏损伤后的再生奠定重要基础。

 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.