キネシン関連モーターのモータードメインの結晶構造
E P Sablin1, F J Kull, R Cooke
1Department of Biochemistry/Biophysics, University of California, San Francisco, California 94143, USA.
Nature
|April 11, 1996
まとめ
キネシンモーターはマイクロチューブルに沿って動きます. ncdとkinesinのモータードメインの構造的な比較は,保存された特徴を明らかにし,共有されたマイクロチューブル結合部位と方向的運動のための共通のメカニズムを示唆しています.
科学分野:
- 分子生物学は分子生物学である.
- 細胞のダイナミクス
- 構造生物学 構造生物学とは
背景:
- キネシン超家族モーターのような微小管ベースのATPアゼは,細胞機能にとって極めて重要です.
- キネシンとncd (キネシンに関連するモーター) は,そのモーター領域における重要なシーケンスの同一性にもかかわらず,マイクロチューブルに沿って反対方向の動きを示します.
研究 の 目的:
- ドロソフィラ ncdモータードメインの結晶構造を決定する.
- 運動領域のncdとkinesinの構造を比較する.
- キネシンとNCDにおける運動の対極性のモデルを提案する.
主な方法:
- ドロソフィラ ncdモータードメインのMgADP複合体の2.5A結晶構造を決定するためのX線結晶学.
- 構造を既知のキネシン構造と比較する.
- 他のNTPases (ミオシン,Gタンパク質) との機能的および構造的比較.
主要な成果:
- NCDとキネシン運動領域は,構造的に非常に類似しています.
- 保存された表面アミノ酸の位置は,NCDとキネシンの共通のマイクロチューブル結合部位を示唆しています.
- 構造的および機能的比較は,様々なNTP段階におけるNTPとNDP状態の間の構成変化の保存されたメカニズムを示しています.
結論:
- 一般的なガンマ・フォスファート感知機構をキネシンとNCDの運動の対極性へと変換するための一般的なモデルが提案されています.
- この発見は,キネシン超ファミリーモーターの方向性運動の分子基礎についての洞察を提供します.
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