Cdc25から14-3-3の放出を調節するPP2A/B56デルタフォスファタゼの役割,ミトーシスの制御
Seth S Margolis1, Jennifer A Perry, Craig M Forester
1Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA.
Cell
|November 18, 2006
まとめ
DNAダメージチェックポイントは,ミトーシス活性化剤Cdc25を制御することによって細胞分裂を調節します. この研究では,PP2A/B56デルタフォスファタゼと14-3-3タンパク質の相互作用がCdc25を活性化し,細胞サイクル進行を促進する方法を明らかにしています.
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:
- DNA受容性チェックポイントは,DNA損傷後の細胞サイクル進行を防ぐために不可欠です.
- ミト細胞活性化剤Cdc25は,阻害性リン酸化と14-3-3タンパク質結合によって調節される.
- ミトスの侵入には,14-3-3タンパク質の除去と,Cdc25のセル287.7での脱リン酸化が必要です.
研究 の 目的:
- Cdc25.のDNA反応チェックポイント制御におけるPP2A/B56デルタフォスファタゼの役割を調査する.
- Cdc25がミトスの侵入を促進するために活性化されるメカニズムを解明する.
主な方法:
- PP2A/B56delta.によってCdc25の脱リン酸化を調査した.
- Cdc25.0への14-3-3結合におけるT138リン酸化の役割を分析した.
- 14-3-3の"シンク"の形成を,中間のフィラメントタンパク質を用いて調べました.
主要な成果:
- DNA応答性チェックポイントは,T138で,Ser287.7と異なるCdc25をデフォスフォリレートするためにPP2A/B56deltaを活性化します.
- T138のリン酸化は必要ですが,Cdc25.から14-3-3の放出には不十分です.
- 中間光線タンパク質によって形成された14-3-3"シンク"とCdc25-14-3-3の相性低下はCdc25の活性化に寄与する.
結論:
- PP2A/B56deltaは,Cdc25を調節するDNA反応チェックポイントの重要な効果因子である.
- 14-3-3の"沈没"とタンパク質の相性変化を含む新しいメカニズムが,Cdc25の活性化とミトスの侵入を制御します.
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