在MYBPC3中发生过早终结的Codon突变会通过慢性激活无意中介衰变引起缩性心肌病
Timon Seeger1,2, Rajani Shrestha1,2, Chi Keung Lam1,2
1Stanford Cardiovascular Institute (T.S., R.S., C.K.L., C.C., W.L.M., E.L., A.W., M.G, J.L., A.O., S.L., H.Y., M.M., M.W., E.A.A., I.K., J.C.W.), Stanford University School of Medicine, CA.
Circulation
|December 28, 2018
概括
MYBPC3中的突变通过激活无意中介衰变导致心脏细胞中异常的处理导致过度缩小的心肌病 (HCM). 抑制这种途径使患者细胞的心脏功能正常化.
科学领域:
- 心血管生物学
- 干细胞生物学
- 分子遗传学
背景情况:
- 缩性心肌病 (HCM) 通常是由MYBPC3突变引起的,导致过早终止的密码体 (PTC).
- MYBPC3 PTC突变诱导HCM的确切机制尚不清楚.
- 这项研究使用人类诱导的多能干细胞衍生心肌细胞 (iPSC-CMs) 来研究与MYBPC3 PTC突变相关的HCM分子致病性.
研究的目的:
- 阐明 MYBPC3 PTC 突变载体中 HCM 致病的分子机制.
- 研究异常处理和基因表达在HCM发展中的作用.
- 确定MYBPC3脱素不足对HCM的贡献.
主要方法:
- 通过基因组编辑从MYBPC3 PTC突变的HCM患者生成同位素IPSC线.
- 对iPSC-CM进行全面的表型和转录组分析.
- 研究无意中介衰变 (NMD) 途径的作用和治疗抑制.
主要成果:
- HCM iPSC-CM患者表现出异常的处理与长时间的衰变和增加的透析,没有结构或收缩缺陷.
- 减少了MYBPC3mRNA,但可比的蛋白质含量表明没有显著的MYBPC3脱不足.
- 观察到无意中介的衰变通路激活和心脏基因表达失调,构成体外HCM特征.
- 抑制NMD逆转分子表型和正常化处理.
结论:
- 在 iPSC- CM 中的 MYBPC3 PTC 突变会导致异常的信号传递和独立于 MYBPC3 脱的分子失调.
- 这项研究提供了第一个直接将无意中介衰变途径的慢性激活与HCM发展联系在一起的证据.
- 针对NMD途径为HCM提供了潜在的治疗策略.
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