Piezo1チャネルの構造とメカニズム
Qiancheng Zhao1,2,3, Heng Zhou1,2, Shaopeng Chi1,2,3
1School of Pharmaceutical Sciences or Life Sciences, Tsinghua University, Beijing 100084, China.
Nature
|February 23, 2018
まとめ
研究者らは 機械的な力を感知するのに 重要なピエゾ1チャネルの構造を明らかにしました この発見により 独特のプロペラのような形状と 機械伝達のためのレバーのようなメカニズムが明らかになり 細胞力学の理解が進んでいます
科学分野:
- バイオ物理学
- 分子生物学
- 細胞生物学
背景:
- メカノセンシティブのピエゾチャネルは,細胞の機械的感知に不可欠です.
- ピエゾ運河の詳細な構造とゲートメカニズムは 捉え難いままです
研究 の 目的:
- マウスPiezo1チャネルの高解像度構造を決定する.
- ピエゾ1媒介メカニカルトランスデュークションの基礎となる分子成分とメカニズムを解明する.
主な方法:
- 電子冷凍顕微鏡 (cryo-EM) を用いてマウスPiezo1の構造を解析した.
- メカニカルトランスデュークションにおける特定された構造成分の役割を調査するために,機能的測定が行われました.
主要な成果:
- この研究では,ピエゾ1マウスの3刃のプロペラのような冷凍EM構造を決定した.
- 9つの重複性トランスメブランヘリカルユニット (THU) が折りたたまれたブレードに組み合わされ,最終的なヘリクスは孔を形成します.
- 中央の細胞内ビームのような構造は,レバーのような動きを容易にし,THUを毛穴に接続し,機械的なゲーティングを可能にします.
結論:
- Piezo1は独特の38トランスメブランヘリックストポロジーを持ち,独特のメカニカルトランスデュークション要素を持っています.
- 細胞内ビームとTHUを含むレバーのようなメカニズムは,機械的刺激に対するPiezo1の反応を制御します.
- 細胞外回路や細胞内ビームの 障害はPiezo1の 機械的活性化を阻害し 提案されたゲーティングモデルを検証します
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