Novel Mechanism of RBFox1 Mediated RNA Metabolism in Heart Failure

项目总结 RNA代谢从合成、加工、翻译到降解是基因的一个组成部分 最终决定心脏转录组整体复杂性和重编程的调控 心力衰竭。RNA结合蛋白是RNA新陈代谢的每个过程的中心，因此建立 它们在心力衰竭的发生和发展中的作用应该导致新的疾病机制和潜在的 治疗靶点。PI(陈高博士)早先的报告揭示了全球RNA剪接的变化 是心力衰竭时心脏转录组重新编程的重要组成部分。此外，这种像胎儿一样的RNA- 剪接重编程受RBFOX1调控，RBFOX1是一种肌肉丰富的RNA剪接因子。然而，在一项新的研究中， PI发现，心脏RBFOX1基因还编码胞质亚型(RBFox1c)，这是由于其自身的替代mRNA 拼接。而核RBFox1n通过全球替代参与心肌肥厚反应 胞浆RBFox1c在心脏病理中的功能作用 还有待探索。在体外和体内的初步研究中，Pi发现胞浆RBFox1c发挥了 应激心脏促炎症基因表达减少在心脏重塑中的关键作用 肌肉细胞。这项建议旨在描述RBFox1c在心脏病中的非规范功能 RBFox1c介导的心脏转录后调控机制的研究进展它还 概述了陈高博士完成博士后培训的广泛职业发展计划 易行博士的监督和向独立调查员的转变配备了独一无二的 研究技能、科学洞察力和极具前景的研究流水线的结合。 在这项提案的K99阶段，PI将表征RBFox1c在心脏中的功能影响 遗传性小鼠模型和体外培养心肌细胞的纤维化反应。的第二个目标 K99期是确定RBFox1c介导的炎症基因抑制的分子机制。 在R00阶段，PI将表征RBFOX1在心脏生理学和心脏生理中的异构体特异性影响 利用异构体特异性操纵的小鼠模型进行病理重塑。私人投资公司还将探索后- RBFox1c通过BRIC-Seq、Trap-Ribo-Seq和Ribo-Seq介导的心脏转录调控机制 MicroRNA竞争分析。拟议中的实验将创造令人兴奋的新机会 在心脏生物学中一个重要但极未被探索的领域的发现，新的洞察力也将填补 目前对病理性心脏重塑发病机制认识上的重要空白 压力。

PROJECT SUMMARY RNA metabolism from synthesis, processing, translation to degradation is an integrated part of gene regulation that ultimately determines the overall cardiac transcriptome complexity and reprogramming during heart failure. RNA binding proteins are central to every process of RNA metabolism and therefore establishing their roles in the onset and progression of heart failure should lead to novel disease mechanisms and potential therapeutic targets. Earlier reports by the PI (Dr. Chen Gao) have revealed that global RNA splicing changes are important part of cardiac transcriptome reprogramming in failing heart. Furthermore, this fetal-like RNA- splicing reprogramming is regulated by RBFox1, a muscle enriched RNA splicing factor. However, in new study, PI found cardiac RBFox1 gene also encoded a cytosolic isoform (RBFox1c) due to its own alternative mRNA splicing. While the nuclear RBFox1n contributes to cardiac hypertrophic response through global alternative splicing regulation as demonstrated by the PI, the functional role of the cytosolic RBFox1c in cardiac pathology is yet to be explored. In preliminary studies both in vitro and in vivo, PI found the cytosolic RBFox1c played a critical role in cardiac remodeling associated with reduced pro-inflammatory gene expression in stressed heart muscle cells. This proposal aims at characterizing the non-canonical function of RBFox1c in cardiac disease progression and exploring the RBFox1c mediated post-transcriptional regulatory mechanism in heart. It also outlines an extensive career development plan for Dr. Chen Gao to complete postdoctoral training under the supervision of Dr. Yi Xing and to transition into an independent investigator well equipped with a unique combination of research skills, scientific insights and highly promising research pipeline. During the K99 phase of this proposal, the PI will characterize the functional impact of RBFox1c in cardiac fibrotic response using both genetic mouse model and in vitro cultured cardiomyocytes. The second aim of the K99 phase is to determine the molecular mechanism of RBFox1c mediated inflammatory gene repression. During the R00 phase, the PI will characterize isoform specific impact of RBFox1 in cardiac physiology and pathological remodeling using isoform specific manipulated mouse models. The PI will also explore the post- transcriptional regulatory mechanisms mediated by RBFox1c in heart through BRIC-Seq, TRAP ribo-seq and microRNA competition analysis. The proposed experiments will create exciting new opportunities of fundamental discovery in an important yet vastly under-explored area in cardiac biology, and new insight will also fill an important gap in the current understanding to the pathogenesis of cardiac remodeling induced by pathological stress.