A Tbx5-Atp2a2 gene regulatory network for cardiac rhythm - Resubmission 01

摘要 房颤(房颤)是最常见的心律失常，与显著的死亡率和 发病率。房颤的特征是由于心脏的随机电活动而出现不规则的心跳，并影响 在美国有300-500万人。临床和介入治疗有中度 有效，并与严重的副作用有关。有一个个体的基因成分 房颤的易感性还没有完全了解。因此，我们实验室对 了解心律失常的遗传基础，特别是通过识别相关基因 参与成人心律的调节网络。我们的实验室发现成人中Tbx5的缺失 小鼠心脏导致自发性房颤，因此确定T-box转录因子在 维持房性心律。野生型和TBX5-KO左心房PolA缺失RNA的深度测序 确定钙调节基因的候选转录因子依赖的顺式调控元件(CRE)， 包括Atp2a2，它们在体外荧光素酶反应试验中得到验证。我们还感兴趣的还有 阐明了与该Cre相关的ncRNA的需求。我们假设依赖于Tbx5的 Atp2a2上ncRNA定义的Cre和ncRNA本身是Atp2a2表达和细胞钙所必需的 动态平衡。定义这些心律调节网络可能有助于在 心律失常的风险，并提供对新的治疗发现的洞察。

Abstract Atrial Fibrillation (AF) is the most common cardiac arrhythmia and is associated with significant mortality and morbidity. AF is characterized by irregular heartbeats due to random electrical activity in the heart, and affects between 3-5 million individuals in the United States. The clinical and interventional therapies have moderate efficacy and are associated with serious side effects. There is a genetic component to an individual's predisposition for AF that is not fully understood. Therefore, our laboratory is particularly interested in understanding the genetic basis for cardiac arrhythmias, particularly through the identification of relevant gene regulatory networks involved in adult cardiac rhythm. Our lab has found that the deletion of Tbx5 from the adult mouse heart leads to spontaneous AF, therefore establishing the importance of the T-box transcription factor in maintaining atrial rhythm. The deep sequencing of polyA-depleted RNA from wild-type and TBX5-KO left atria identified candidate transcription factor dependent cis-regulatory elements (CREs) for calcium handling genes, including Atp2a2, which were validated in an in vitro luciferase response assay. We are also interested in elucidating the requirement of the ncRNA associated with this CRE. We hypothesize that the Tbx5-dependent ncRNA-defined CRE at Atp2a2, and the ncRNA itself, are required for Atp2a2 expression and cellular calcium homeostasis. Defining these cardiac rhythm regulatory networks may aid in the identification of individuals at risk for arrhythmia, and provide insight into new therapeutic discovery.