Transcriptional mechanisms of atrial fibrillation

摘要 患者的遗传分析有相关的转录因子(TF)，这是一种调节基因的蛋白质 表现为心房颤动(房颤)。房颤是主要的医疗负担，伴随着相关的医疗成本 在美国每年超过260亿美元。房颤会加重多种形式的心脏病，是 中风的主要原因。由于房颤的发病率随着年龄的增长而增加，房颤造成的人员和经济损失是 预计将继续增加。目前的治疗方法可以减轻房颤的后果，但没有 预防或专门治疗房颤的疗法。迫切需要新的治疗方式。 全基因组关联研究已经将房颤与几个TF联系起来，其中包括TBX5。TFS维护 健康细胞中的基因表达程序，以及转铁蛋白网络行为的错误导致不适当的 促进心房重构和房颤的基因表达水平。尽管已经取得了重大进展 在识别组成心房基因调控网络(GRN)的转录因子和下游靶点时 心肌细胞(CMS)在健康和房颤中的许多调控机制尚不清楚。 我们的初步数据显示，TBX5和TEAD1之间存在以前未被认识到的相互作用。TEAD1是一个TF 目前最为人所知的是转录共激活因子YAP1的主要合作伙伴，YAP1调节细胞生长 以及通过河马信号通路对机械力的反应。此外，初步数据显示， 表明我们已经通过在心房CMS中灭活Tbx5成功地产生了小鼠房颤模型 腺相关病毒介导的NPPA启动子驱动的Cre重组酶转基因。以这些结果为基础， 在这里，我们建议检验以下假设：TBX5-TEAD1复合体在 健康的心房，而TBX5的缺失导致房颤的部分原因是允许不适当的转录激活 PYAP-TEAD1.在目标1中，我们采用生化和遗传方法来确定TBX5、TEAD1、 与YAP相互作用，调节房颤的发病。在目标2中，使用TEAD1 CHIP-SEQ、单核RNA-SEQ、 和单核ATAC-seq，我们将揭示驱动房颤的转录调控的变化 发病机制。 提出的研究将有助于我们理解房颤的发病机制，并提供很大的参考价值。 让PI有机会接受分子心脏病学和功能基因组学方法的培训 基因调控。作为这项培训的组成部分，PI将精通最新的尖端方法 以及作为一名独立调查员的职业生涯所必需的技术。的第二个目标 提案特别侧重于获取和分析NGS数据，以及由 Pu实验室小组(包括两名专门的生物信息学家)和附属哈佛医学院 提供了一个独特的机会，通过探索数据来发展这些技能，并得到 通过课堂和与同龄人的协作互动。

ABSTRACT Genetic analyses of patients have associated transcription factors (TFs), proteins which regulate gene expression, with atrial fibrillation (AF). AF is a major healthcare burden with associated healthcare costs exceeding 26 billion dollars in the US annually. AF exacerbates many forms of heart disease and is among the leading causes of stroke. Since AF incidence increases with age, the human and financial toll of AF is anticipated to continue to increase. Current therapies mitigate the consequences of AF, but there are no therapies that prevent or specifically treat AF. New treatment modalities are urgently needed. Genome-wide association studies have linked AF to several TFs, among them TBX5. TFs maintain gene expression programs in healthy cells, and errors in the behavior of the TF network result in inappropriate levels of gene expression that promote atrial remodeling and AF. Although significant progress has been made in identifying TFs and downstream targets that comprise the gene regulatory networks (GRNs) of atrial cardiomyocytes (CMs), many of the regulatory mechanisms of atrial CMs in health and AF remain unknown. Our preliminary data reveal a previously unappreciated interaction between TBX5 and TEAD1. TEAD1 is a TF currently best known as a major partner of the transcriptional co-activator YAP1, which regulates cell growth and responses to mechanical forces through the Hippo signaling pathway. Furthermore, the preliminary data show that we have successfully generated a murine AF model by inactivating Tbx5 in atrial CMs by delivering an Nppa promoter-driven Cre recombinase transgene using adeno-associated virus. Building on these results, here we propose to test the hypothesis that the TBX5-TEAD1 complex maintains rhythm homeostasis in healthy atria, while the loss of TBX5 causes AF in part by permitting inappropriate transcriptional activation by pYAP-TEAD1. In Aim 1, we implement biochemical and genetic approaches to determine how TBX5, TEAD1, and YAP interact to modulate AF pathogenesis. In Aim 2, using TEAD1 ChIP-seq, single nucleus RNA-seq, and single nucleus ATAC-seq, we will uncover changes in transcriptional regulation that drive AF pathogenesis. The proposed research will contribute to our understanding of AF pathogenesis and provide a great opportunity for the PI to become trained in molecular cardiology and functional genomics approaches to study gene regulation. Integral to this training, the PI will become well-versed in the latest cutting-edge approaches and technologies that are essential for an independent career as an investigator. The second aim of the proposal particularly focuses on obtaining and analyzing NGS data, and the training environment offered by the Pu lab group (which includes 2 dedicated bioinformaticians) and the affiliated Harvard Medical School offers a unique opportunity to develop these skills by exploration of the data, supported by didactic training in the classroom and by collaborative interactions with peers.