ダイネインとキネシンモータータンパク質の,タウによる異なる調節
Ram Dixit1, Jennifer L Ross, Yale E Goldman
1Department of Physiology and Pennsylvania Muscle Institute, University of Pennsylvania, Philadelphia, PA 19104, USA.
Science (New York, N.Y.)
|January 19, 2008
まとめ
タウのような微小管に関連するタンパク質は,モータータンパク質の動きに差異的に影響する. タウはキネシンが分離し,ダイネインが方向を逆転させ,軸索輸送を調節する.
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.
- バイオフィジックス 生物物理学
背景:
- ディネインとキネシンは,マイクロチューブルに沿って細胞内輸送に不可欠な運動タンパク質です.
- タウのようなマイクロチューブル関連タンパク質 (MAP) は,神経細胞に豊富に存在し,運動タンパク質と相互作用する.
- これらの相互作用を理解することは,軸索輸送の動態を理解するために不可欠です.
研究 の 目的:
- ダイネインおよびキネシン運動タンパク質の運動性に対するタウの影響を調査する.
- タウ結合がこれらの運動タンパク質の方向的運動とプロセシビティにどのように影響するか解明する.
主な方法:
- 単一分子の研究は,タウで飾られた微小管のモータータンパク質の行動を観察するために使用されました.
- モータータンパク質の阻害に対するタウの濃度に依存する効果を定量化した.
主要な成果:
- ダイネイン運動タンパク質は,タウと接触すると方向を逆転する傾向を示した.
- キネシン運動タンパク質はタウに対してより敏感であり,しばしばタウのパッチのマイクロチューブルから離れる.
- Tauのマイクロチューブル結合領域は,運動活動を抑制するのに十分であり,ダイネインよりもはるかに低いtau濃度でキネシン阻害が発生しました.
結論:
- タウのような微小管に関連するタンパク質は,ダイネインとキネシンの運動性を差異的に調節することができます.
- この微分調節は,MAPが神経細胞の微小管に依存した軸索輸送を空間的に制御するメカニズムを示唆している.
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