Ptpn23は,ディストロフィン-グリコタンパク質複合体の組み立てを促進することによって,心臓T管のパターンを制御する
Chen Xu1,2,3, Ge Zhang1,2,3, Xinjian Wang1,2,3
1Center for Genetic Medicine, The Fourth Affiliated Hospital (C.X., G.Z., X.W., X.H., J.Z., S.H., R.X., F.H., P.H.), Zhejiang University School of Medicine, Hangzhou, China.
Circulation
|January 12, 2024
まとめ
非受容体型23型 (Ptpn23) のタンパク質チロシンフォスファタゼは,心臓のT管構造に不可欠です. Ptpn23の喪失はT管を壊し,拡張心筋病と心機能障害を引き起こす.
科学分野:
- 心血管生物学
- 細胞生物学
- 分子心臓科
背景:
- 心臓の横管 (T管) は刺激-収縮結合に不可欠である.
- T管の組織は,コスタメア経由でサルコメリックZ盤に固定される.
- ディストロフィン・グリコタンパク質複合体 (DGC) はコスタメアの重要な成分ですが,T管の形成におけるその役割は不明です.
研究 の 目的:
- 心臓のT管の形成と維持におけるタンパク質チロシンフォスファタゼ,非受容体型23 (Ptpn23) の役割を調査する.
- Ptpn23がコスタメレスとDGCと相互作用する分子メカニズムを解明する.
主な方法:
- Cre/LoxpとCRISPR/Cas9を用いて,心筋細胞特異のPtpn23とα-アクチニン-2ノックアウトマウスを生成した.
- AAV9をインビボ遺伝子編集とモザイク体変異に利用した.
- 電子顕微鏡と光染色 (Di-8-ANEPPS,Cav3) を用いてT管構造を評価した.
- グリセロール・グラデント分化とSDS-PAGEによるDGCアセンブリとタンパク質の相互作用を分析した.
主要な成果:
- 拡張性心筋病患者およびマウスにおけるPtpn23発現の低下を観察した.
- Ptpn23の欠失により,T管の組織が崩れ,進行的な拡張性心筋症になり,T管の直径が大きくなった.
- Ptpn23は,T管を固定するためにα-アクティニンとディストロフィンと相互作用し,コスタメアの完全性にとって不可欠です.
- Ptpn23ノックアウトマウスで観察されたディストロフィンフェノコピーされたT管の欠陥の喪失.
結論:
- Ptpn23は心臓のT管の形成と維持に不可欠です.
- Ptpn23はコスタメアでDGCの組み立てを調整し,適切なT管のパターニングのためにα-アクティニンと相互作用する.
- Ptpn23は,心臓発達の過程でT管の形状を形作るのに細胞自律的な役割を果たします.
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