13SコンデンシンをCdc2によってリン酸化および活性化 in vitro
K Kimura1, M Hirano, R Kobayashi
1Cold Spring Harbor Laboratory, Post Office Box 100, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.
Science (New York, N.Y.)
|October 17, 1998
まとめ
クセノプス (Xenopus) の卵エキスのミトーシス染色体凝縮は13S凝縮に依存しています. Cdc2キナーゼによるリン酸化は,この複合体を活性化させ,染色体の凝縮を誘発する上で重要な役割を果たすことを示唆する.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- 13Sコンデンシンは,Xenopusの卵エキスのミト性染色体凝縮のための重要なタンパク質複合体です.
- この複合体はDNAと相互作用することが知られており,細胞周期中に調節されます.
研究 の 目的:
- 13Sコンデンシンが染色体凝縮を誘発するメカニズムを調査する.
- ミトーシス中の13Sコンデンシン活性化に関与する調節因子と経路を特定する.
主な方法:
- クセノプスの卵エキスから13Sコンデンシンを浄化する.
- ATPとトポイソメラーゼIの存在下でのDNA超巻き活性を評価するためのインビトロアッセイ.
- ミトーシス特有のリン酸化実験と免疫低下の研究.
- XCAP-D2サブユニットのリン酸化部位を特定するためのペプチドマッピング.
主要な成果:
- 浄化された13SコンデンシンがDNAに陽性スーパーコイルをインビトロで導入することが示されました.
- 13Sコンデンシンのスーパーコイリング活動は,ミトーシス特有のリン酸化によって調節されていることが判明しました.
- Cdc2キナーゼは,13Sコンデンシンをリン酸化および活性化させる可能性が高い酵素として特定されました.
- 複数のCdc2リン酸化部位は,XCAP-D2サブユニットのカルボキシル末端ドメインに局在していた.
結論:
- Cdc2キナーゼによる13Sコンデンシンのリン酸化は,重要な調節イベントである.
- このリン酸化イベントは,ミトック染色体凝縮の開始を in vitro で引き起こすと提案されています.
- この発見は,細胞分裂中の染色体分離の過程における重要なステップを明らかにしています.
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