バクテリアのエフェクターVopLは,アクチンを糸状の構造に編成します

Jacob A Zahm¹, Shae B Padrick, Zhucheng Chen

¹Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.

Cell

|October 15, 2013

まとめ

Vibrio parahaemolyticus VopL タンパク質はビブリオ・パラヘモリチカスのタンパク質であるため

科学分野:

微生物学微生物学とは
細胞生物学細胞生物学
構造生物学構造生物学とは

背景:

Vibrio parahaemolyticus VopLはエフェクタータンパク質である.
VopLはアクチン繊維を核化し,VopLのC端領域 (VCD) と3つのWASPホモロジー2 (WH2) モチーフを持っています.

研究の目的:

アクチンに結合したVCDダイマーの結晶構造を決定する.
VopL媒介のアクチン核形成のメカニズムを解明する.

主な方法:

X線結晶グラフィーです.
アクチンに結合したVopL C末端領域 (VCD) の構造分析.

主要な成果:

結晶構造は,VCDダイマーが3つのアクチンモノマーをフィラメントのような配列に編成していることを明らかにします.
WH2モチーフは,ステリック障害なしにこれらのアクチン単体と結合することができます.
この組織は,新しいアクチンサブユニット追加のテンプレート作成を容易にする.

結論:

VopLは,VCDとWH2モチーフによって提供されるモノマーによって組織されたフィラメントのような構造を作り,アクチンを核化する.
このメカニズムは,Arp2/3複合体とforminsによるアクチン核化に類似しています.
モノメアを糸状の構造に編成することは,アクチン核形成の重要な特徴です.

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