转录失调是单基性心律失常综合征和心脏再极化常见修饰物的基础
Kevin R Bersell1, Tao Yang2, Jonathan D Mosley1
1Departments of Pharmacology (K.R.B., A.M.G., D.O.K., K.K., J-E.S., C.C.C., Q.S.W., S.P., B.C.K., D.M.R.), Vanderbilt University, Nashville, TN.
Circulation
|December 16, 2022
概括
一种罕见的TBX5基因变异通过减少SCN5A转录和破坏PDGF信号,导致心律失常. 这揭示了皮律失常的新机制,涉及PI3K信号受损.
科学领域:
- 心血管遗传学
- 分子心脏病学
- 系统生物学
背景情况:
- 布鲁加达综合征 (BrS) 是一种与SCN5A基因突变相关的遗传性心律失常.
- 鉴定出一种BrS家族和一种罕见的TBX5- G145R变异,缺乏SCN5A突变.
研究的目的:
- 调查TBX5-G145R变异在布鲁加达综合征发病过程中的作用.
- 阐明潜在的分子和电生理机制.
主要方法:
- 来自TBX5- G145R患者的诱导多能干细胞 (iPSCs).
- 用于电生理学和转录学分析,将IPSC分化为心肌细胞 (iPSC-CM).
- 使用CRISPR/Cas9进行基因校正,并研究PDGF/PI3K通路.
主要成果:
- 该TBX5-G145R变体降低了转录活性,导致峰值降低和晚期电流增强 (INa).
- 这与直接的SCN5A下调和PDGF受体介导的PI3K信号受损有关.
- 在人体中,PDGF受体阻塞延长了作用潜力,PDGF水平与QTc间隔相反相关.
结论:
- 通过减少SCN5A转录,TBX5变种可以引起BrS.
- 发现了一种涉及破坏PDGF-PI3K信号的新型心律失常机制,导致晚期电流的增强.
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