MIS12複合体の構造とCENP-Cとの相互作用の分子基礎
Arsen Petrovic1, Jenny Keller1, Yahui Liu1
1Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany.
Cell
|November 25, 2016
まとめ
研究者らは,CENP-Cに結合するMIS12複合体 (MIS12C) の構造を明らかにし,染色体とミクロチューブルを結びつける方法を明らかにした. この発見は染色体分離とミトスのチェックポイント機能を理解するのに役立ちます.
科学分野:
- 細胞生物学
- 構造生物学
- 分子生物学
背景:
- キネトコアは,細胞分裂時に正確な染色体分離のために染色体をスパインドルマイクロチューブルと結びつける重要なタンパク質複合体である.
- KMN (KNL1,MIS12,NDC80) アセンブリは,KMNをCENP-C経由で近辺領域に接続するために不可欠なMIS12複合体である.
- MIS12Cの橋渡し機能の構造的基盤は未だに曖昧である.
研究 の 目的:
- MIS12複合体のCENP-Cとの相互作用の構造的基礎を解明する.
- MIS12C-CENP-Cの相互作用を調節するAurora Bキナーズの役割を調査する.
- KMNアセンブリの包括的な構造モデルを構築する.
主な方法:
- CENP-C断片との複合体におけるヒトMIS12Cの構造を決定するために,X線結晶学を用いた.
- オーロラBキナーゼによるMIS12C- CENP- C相互作用の調節を研究するために生化学的測定法を使用した.
- KNL1CとNDC80Cの既存の高解像度構造と新しい構造データを統合する.
主要な成果:
- CENP- Cの断片に結合したMIS12Cの結晶構造が決定され,この相互作用の分子詳細が明らかになった.
- この研究では,MIS12C- CENP- Cの相互作用を調節するAurora Bキナーズの作用が確認されました.
- 新しい構造データと既存の構造データを組み合わせて,KMNアセンブリのほぼ完全な構造モデルが構築されました.
結論:
- 決定された構造は,キネトコア内のMIS12Cのブリッジ機能に関する重要な洞察を提供します.
- オーロラBキナーゼによるMIS12C-CENP-C相互作用の調節を理解することは,ミトスのチェックポイント制御を理解する上で鍵となる.
- 総合的なKMN組立モデルは,染色体分離に不可欠な保存された機械に関する私たちの知識を向上させます.
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