Munc18によるエクソサイトーシス中の融合孔ダイナミクスの制御

R J Fisher¹, J Pevsner, R D Burgoyne

¹Physiological Laboratory, University of Liverpool, Crown Street, Liverpool, L69 3BX, UK.

Science (New York, N.Y.)

|February 7, 2001

まとめ

Munc18-1タンパク質は,SNAREタンパク質と相互作用することで,エクソサイトーシスを調節する. Munc18-1の変異体が融合孔の膨張を加速し,末期の膜融合におけるその役割を示している.

科学分野:

細胞生物学細胞生物学
神経科学は神経科学である.
バイオケミストリーバイオケミストリー

背景:

細胞内膜融合は,SNAREタンパク質に依存しています.
ニューロンのMunc18-1 (nSec1) のようにSec1タンパク質ファミリーのメンバーは,膀の輸送と調節されたエクソサイトーシスに不可欠です.

研究の目的:

エキゾシトの放出の運動学におけるMunc18-1の役割を調査する.
膜融合の最終段階におけるMunc18-1の機能を決定する.

主な方法:

アドレナルのクロマフィン細胞におけるシンタキシン afinity が低下したMunc18-1変異体の発現.
シングル・グラヌル系エクソサイト放出イベントの分析.

主要な成果:

Munc18-1変異体は,エクソサイトの放出の動態を変化させた.
この突然変異は,核融合孔の膨張を加速させ,後期の核融合段階における役割を示唆している.
シンタキシンからのMunc18-1解離は,融合後の動力の重要な決定因子として特定されました.

結論:

Munc18-1は,細胞内膜融合の遅い段階で重要な役割を果たしています.
Munc18-1のシンタキシンからの解離は,エクソサイトーシス中の融合後のイベントの速度を制御する.

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