A Novel Role for NFATC1 in Modulating Cardiac Excitability

项目摘要/摘要 这项提议的总体目标是探索NFATC1作为一种新的分子和电生理作用 心房颤动(房颤)易感基因及NFATC1在房颤中的作用 兴奋性。房颤是临床上最常见的持续性心律失常，有经济负担。 每年的医疗保健费用超过70亿美元。新出现的证据表明，心脏转录因子在 普通人群房颤和房颤两种家族性形式的发病机制。我们发现了一种突变 心脏转录因子NFATC1是由年轻发病的房颤定义的犹他州高危家系。NFATC1是一种钙离子 依赖转录因子被认为在心脏发育中发挥作用，但到目前为止从未被认为是 与心脏兴奋性有关。我们令人兴奋的初步数据确定了NFATC1在调控中的一个新角色 心房兴奋性，在nFATc1缺失斑马鱼发生自发性房性快速性心律失常和幼年突然 死亡。目的1确定突变型NFATC1的生化、分子和电生理基础 功能障碍，使用HL-1心房细胞系，一种人类细胞培养模型(患者特定和基因组编辑) 诱导多能干细胞来源的心肌细胞(IPSC-CMS)和全动物模型(转基因 斑马鱼)。目的探讨NFATC1在调节心房兴奋性中的作用。 NFATc1基因缺失的斑马鱼发生房性快速性心律失常的电生理基础。AIM 3将定义NFATC1- 调控心脏兴奋性的转录网络和基因通路，使用单细胞RNA- 人心房中的SEQ、CHIP-SEQ和CHIP-MS以及NFATC1缺失和WT IPSC-CMS。 我们的方案利用了人类遗传学、基因组编辑技术、最先进的下一代测序技术 模式和生物信息学，以及电生理学，全面表征NFATC1的新角色 在心脏兴奋性和房颤发病机制中的作用。对调控离子的关键转录网络的理解 通道基因表达和心房兴奋性将提供更广泛、更全面的理解 降低心律失常的易感性，为房颤的新疗法奠定基础。

PROJECT SUMMARY / ABSTRACT The overall goal of this proposal is to explore the molecular and electrophysiological role of NFATC1 as a novel atrial fibrillation (AF) susceptibility gene and to define the previously unknown contribution of NFATC1 to atrial excitability. AF, the most common sustained arrhythmia encountered in clinical practice, has an economic burden exceeding $7 billion in annual health care costs. Emerging evidence implicates cardiac transcription factors in the pathogenesis in both familial forms of AF and AF in the general population. We identified a mutation in the cardiac transcription factor NFATC1 in a high-risk Utah pedigree defined by young onset AF. NFATC1 is a Ca2+- dependent transcription factor postulated to play a role in cardiac development, but up until now has never been associated with cardiac excitability. Our exciting preliminary data identify a novel role for NFATC1 in modulating atrial excitability, in that nfatc1 null zebrafish develop spontaneous atrial tachyarrhythmia and juvenile sudden death. Aim 1 seeks to define the biochemical, molecular and electrophysiological basis of the mutant NFATC1 dysfunction, using the HL-1 atrial cell line, a human cell culture model (patient-specific and genome-edited induced pluripotent stem cell derived cardiomyocytes, iPSC-CMs), and a whole animal model (transgenic zebrafish). Aim 2 characterizes the role of NFATC1 in modulating atrial excitability by exploring the molecular and electrophysiological basis for the atrial tachyarrhythmia in nfatc1 null zebrafish. Aim 3 will define NFATC1- controlled transcriptional networks and gene pathways that regulate cardiac excitability, using single-cell RNA- Seq, ChIP-Seq and ChIP-Mass Spectroscopy in human atrium and NFATC1 null and WT iPSC-CMs. Our proposal leverages human genetics, genome-editing techniques, state-of-the-art Next-Gen sequencing modalities and bioinformatics, and electrophysiology to comprehensively characterize the novel role of NFATC1 in cardiac excitability and AF pathogenesis. An understanding of a key transcriptional network that regulates ion channel gene expression and atrial excitability will provide a broader, and more comprehensive understanding of arrhythmia susceptibility and lay the foundation for novel AF therapies.