ブラッシュ・ボーダー・ミオシンIで32度の尻尾の振動でADPが放出される
J D Jontes1, E M Wilson-Kubalek, R A Milligan
1Department of Cell Biology, Scripps Research Institute, La Jolla, California 92037, USA.
Nature
|December 14, 1995
まとめ
ブラッシュ・ボーダー・ミオシンI (BBMI) は,そのATPaseサイクル中に重要なドメインの移動を経験します. BBMIのこの構造の変化は,非伝統的なミオシンであり,ミオシンIIとは異なり,機能的適応を示唆しています.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
背景:
- ブラッシュ・ボーダー・ミオシンI (BBMI) は,腸内マイクロビリに含まれる非従来の単頭のミオシンです.
- 重鎖 (M(r) 119K) と3つのカルモジュリン軽鎖を有している.
- BBMIは構造的な役割があると考えられていますが,アクチン活性化ATPaseと運動性特性を示しています.
研究 の 目的:
- BBMIで飾られたアクチンフィラメントの3次元構造を調査する.
- アクトミオシンATPアゼサイクル中のBBMIの構造変化を分析する.
主な方法:
- BBMIで飾られたアクチン繊維の3次元マッピング.
- 結合されたMgADPと結合されていない構造の比較.
主要な成果:
- BBMIのモータードメインは,硬直性のような状態にとどまっていました.
- ライトチェーン・バインディング・ドメインは,著しい変動 (約. 32度) でした.
- その結果,ミオシンIIと異なる約50-72アングストームの動きが生じた.
結論:
- アクトミオシンATPアゼサイクル中の構造の変化は,異なるミオシンタイプによって異なります.
- これらの違いは,ミオシンの特殊な機能的適応を反映している可能性が高い.
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