Transcriptional mechanisms of atrial fibrillation

摘要 患者的遗传分析有相关的转录因子（TF），调节基因的蛋白质， 表达，伴心房颤动（AF）。AF是一种主要的医疗保健负担，伴随着相关的医疗保健成本 超过260亿美元。房颤会加重多种形式的心脏病， 中风的主要原因。由于AF发病率随年龄增长而增加，因此AF的人力和经济损失是 预计将继续增加。目前的治疗减轻了AF的后果，但没有 预防或特异性治疗AF的新疗法。迫切需要新的治疗方式。 全基因组关联研究将AF与几种TF联系起来，其中包括TBX 5。TF保持 健康细胞中的基因表达程序，以及TF网络行为的错误导致不适当的 促进心房重构和AF的基因表达水平。尽管已经取得了重大进展， 在鉴定转录因子和下游靶点，包括心房肌细胞的基因调控网络（GRNs）， 尽管心房肌细胞（CM）的许多调节机制在健康和AF中仍然是未知的。 我们的初步数据揭示了TBX 5和TEAD 1之间以前未被重视的相互作用。TEAD 1是TF 目前最为人所知的是转录辅激活因子YAP 1的主要伙伴，YAP 1调节细胞生长 以及通过Hippo信号通路对机械力的反应。此外，初步数据 显示我们已经成功地通过在心房CM中失活Tbx 5产生了鼠AF模型， 使用腺相关病毒的Nppa启动子驱动的Cre重组酶转基因。在这些结果的基础上， 在这里，我们提出测试TBX 5-TEAD 1复合物维持节律稳态的假设， 健康的心房，而TBX 5的损失导致AF的部分原因是允许不适当的转录激活， pYAP-TEAD1.在目标1中，我们实施生物化学和遗传方法来确定TBX 5，TEAD 1， 和雅普相互作用以调节AF发病机制。在目标2中，使用TEAD 1 ChIP-seq，单核RNA-seq， 和单核ATAC-seq，我们将揭示驱动AF的转录调控的变化， 发病机制 这项研究将有助于我们了解房颤的发病机制，并提供一个伟大的 PI有机会接受分子心脏病学和功能基因组学方法的培训， 基因调控作为培训的一部分，PI将精通最新的尖端方法 和技术，这是一个独立的职业生涯作为一个调查员。第二个目标 建议特别侧重于获取和分析NGS数据，以及 Pu实验室小组（包括2名专门的生物信息学家）和附属的哈佛医学院 提供了一个独特的机会，通过探索数据来发展这些技能，并得到以下教学培训的支持： 通过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.