人間のWEE1チロシンキナーゼによってp34cdc2-サイクリンB複合体の無活性化
1Department of Physiology, Tufts University School of Medicine, Boston, MA 02111.
Science (New York, N.Y.)
|September 25, 1992
まとめ
ヒトのWEE1遺伝子産物であるチロシンキナーゼは,p34cdc2-サイクリンB複合体を無効化し,ミトーシスへの侵入を調節する. 人間のCdc25Cは,p34cdc2.2.を脱リン酸化することによって,この抑制を逆転させます.
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:
- Schizosaccharomyces pombeのミトーシスへの侵入は,wee1+遺伝子によって制御されています.
- wee1+遺伝子産物は,チロシン15にp34cdc2をリン酸化し,p34cdc2-サイクリンB複合体を無効化する.
研究 の 目的:
- wee1+遺伝子 (WEE1Hu) のヒトホモログの機能を調査する.
- WEE1Huがヒト細胞のp34cdc2-サイクリンB複合体を直接調節するかどうかを判断する.
主な方法:
- バクテリアにおけるWEE1Huの過剰生産.
- 精製されたヒトWEE1キナーゼとp34cdc2-サイクリンB複合体を用いたインビトロキナーゼアッセイ.
- 人間のCdc25Cタンパク質の活性に関するアッセイ.
主要な成果:
- 人間のWEE1キナーゼはチロシン特有である.
- WEE1Huはチロシン15にp34cdc2をリン酸化するが,スレオニン14には非活性化させ,p34cdc2-サイクリンB複合体を非活性化させる.
- 人間のCdc25Cはp34cdc2をデフォスフォリレートし,WEE1媒介による阻害を逆転させます.
結論:
- WEE1Huは,ヒト細胞のp34cdc2-サイクリンB複合体を直接調節する.
- WEE1Huと異なるキナーゼは,スレオニン14でp34cdc2をリン酸化する.
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