結合複合体は,SNAREに依存した膜融合の末端段階を駆動する
Massimo D'Agostino1, Herre Jelger Risselada2,3, Anna Lürick4
1Département de Biochimie, Université de Lausanne, Chemin des Boveresses 155, CH-1066 Epalinges, Switzerland.
Nature
|November 2, 2017
まとめ
結合タンパク質は膜融合における最終的なエネルギー障壁を克服するために不可欠であり,SNARE (溶性N-エチルマレイミド感受因子結合タンパク質受容体) と連携して孔形成を推進する. この協働は 臓器細胞の 生成や運搬などの 細胞プロセスに不可欠です
科学分野:
- 細胞生物学
- バイオ物理学
背景:
- 膜融合は,オルガネルの生殖と膀の運搬を含む真核細胞の機能に不可欠である.
- SNAREのタンパク質複合体は膜融合を推進するコアメカニズムとして知られていますが,最終的な孔形成段階にはエネルギーがかかります.
研究 の 目的:
- 膜融合過程で最終的なエネルギー障壁を克服する際の結合タンパク質の役割を調査する.
- SNARE と結合した結合タンパク質の機械的貢献を明らかにする.
主な方法:
- イースト・バキュオルの in vivoおよびin vitro融合を組み合わせた
- 膜融合プロセスの分子シミュレーション
主要な成果:
- SNAREは単独で半融合を容易にするが,完全な融合孔形成にはならない.
- 結合タンパク質はSNARE複合体の体積を大幅に増加させ,半融合部位を変形させます.
- この変形は,核融合孔を開くためのエネルギーバリアを下げ,必要な推進力を提供します.
結論:
- 結合タンパク質は,毛穴形成に不可欠な膜融合の末期段階で重要な機械的役割を果たします.
- SNAREと結合タンパク質は,膜融合を推進する単一の統合ユニットとして機能する可能性があります.
- 核融合装置は以前より複雑である可能性が高い.
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