62 kdのタンパク質のカルシウムとカルモジュリンに依存したリン酸化は,海のミトーシス器官におけるマイクロチューブルの脱ポリメリゼーションを誘導する
1Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755.
Cell
|June 3, 1988
まとめ
海のミトック装置 (MA) には,62kd基板をリン酸化するタンパク質キナーゼが含まれています. このリン酸化は,ミトーシス中のマイクロチューブル脱ポリメリゼーションを誘発し,細胞分裂に影響を与えます.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- ミトスの器官 (MAs) は細胞分裂に不可欠です.
- タンパク質のリン酸化は,細胞のプロセスを調節する役割を果たします.
- ミトーシス中のMAの安定性を制御する特定のメカニズムは,完全に理解されていません.
研究 の 目的:
- カルシウムおよびカルモジュリンに依存するタンパク質キナーゼの役割を調査するために,海刺MAs.
- 特定の62kd基板のリン酸化がMAの安定性に与える影響を決定する.
- これらの発見がミトーシスのモデルに及ぼす影響を調査する.
主な方法:
- 微小管安定化バッファで海刺MAsを分離する.
- タンパク質のリン酸化を研究するためのインビトロキナーゼアッセイ.
- 生体細胞における基質のリン酸化を確認するためのインビボラベリング研究.
- 顕微鏡でMA微小管のデポリメリゼーションを評価する.
主要な成果:
- カルシウムおよびカルモジュリンに依存するタンパク質キナーゼは,孤立したMAs.で特定されました.
- このキナーゼは,特定の62kDの内生基板をリン酸化する.
- 62kdタンパク質のリン酸化により,10分以内にMAマイクロチューブルの有意なデポリメリゼーションが起こりました.
- 62kdのリン酸化のないMAsは,最大30分間安定したままでした.
- In vivo研究では,ミトーシス中の62 kdタンパク質のリン酸化が確認されました.
結論:
- 特定のタンパク質のリン酸化は,海のMAの安定性を調節する.
- カルシウム/カルモジュリン依存キナーゼによる62 kdタンパク質のリン酸化は,微小管の脱ポリマー化に関連しています.
- この過程は,ミトーシス中のアナフェーズのイベントに役割を果たしている可能性が高い.
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