トランスクリプション不調は,単一性不律症候群と心臓再極化の一般的な修正因子の両方を根底にしている
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
まとめ
希少なTBX5遺伝子変異は,SCN5Aの転写を減らし,PDGFのシグナル伝達を妨害し,心律不整を引き起こす. これはPI3Kシグナル伝達が損なわれるような新しいリズム変異のメカニズムを明らかにした.
科学分野:
- 心血管遺伝学
- 分子心臓科
- システム生物学
背景:
- ブルガダ症候群 (BrS) は,しばしばSCN5A遺伝子変異に関連した遺伝性不律症である.
- BrSとSCN5A変異を欠いた希少なTBX5-G145R変異の家族が特定されました.
研究 の 目的:
- ブルガダ症候群の病原性における TBX5- G145R 変異体の役割を調査する.
- 基礎となる分子と電気生理学的メカニズムを解明する.
主な方法:
- TBX5- G145Rを患った BrS患者の誘発性多能幹細胞 (iPSC) を生成した.
- 電気生理学およびトランスクリプトミア分析のための心筋細胞 (iPSC-CM) に区分されたiPSCs.
- CRISPR/Cas9を用いて遺伝子修正を行い PDGF/PI3K経路を調査した.
主要な成果:
- TBX5- G145R変異は転写活性を低下させ,ピークを減少させ,遅いナトリウム電流 (INa) を増加させた.
- これは,SCN5Aの直接的なダウンレギュレーションと,PDGF受容体媒介のPI3Kシグナル伝達障害に関連していた.
- PDGF受容体阻害は行動ポテンシャルを延長し,PDGFレベルはヒトのQTc間隔と逆相関していた.
結論:
- TBX5の変種は,SCN5Aの転写が低下することで,BrSを引き起こす可能性があります.
- PDGF- PI3Kのシグナル伝達が妨げられ,遅いナトリウム流が増加する新たなリズム変異のメカニズムが特定されました.
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