2つのヒストンマークは,内部のセントロメアと染色体のバイオリエンテーションを確立します
Yuya Yamagishi1, Takashi Honda, Yuji Tanno
1Laboratory of Chromosome Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi, Tokyo 113-0032, Japan.
Science (New York, N.Y.)
|October 9, 2010
まとめ
2つのヒストンキナーゼ,ハスピンとBub1は,染色体旅客複合体 (CPC) を中心粒子の内側に向け,協力して作用する. この正確なターゲティングは,細胞分裂中に適切な染色体分離を保証します.
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.
- 遺伝学 遺伝学とは
背景:
- ミトーシス中の正確な染色体分離は,染色体旅客複合体 (CPC) に依存しています.
- CPCは,オーロラBとサバイヴィンを含んでおり,適切な機能のために,内部のセントロメアに局所する必要があります.
- 内セントロメアを定義し,CPCの局所化を指示する分子機構は,ほとんど解明されていないままである.
研究 の 目的:
- 染色体旅客複合体 (CPC) の中枢粒子の内側へのターゲティングの基礎となる分子メカニズムを調査する.
- 内セントロメアを定義し,CPCを勧誘する重要な要因と修正を特定する.
主な方法:
- 分裂酵母とヒト細胞モデルを使用した.
- 研究されたヒストンの改変,特にヒストンH3-スレオニン3 (H3-pT3) のハスピンによるリン酸化とヒストン2A-セリン121 (H2A-S121) のBub1.1によるリン酸化.
- 改変された核個体とCPC成分 (サバイヴィン) とアダプタ (シュゴシン) の結合相互作用を分析した.
- Haspin,Bub1,cohesin,およびPds5の細胞内の位置を調べました.
主要な成果:
- ハスピン媒介のH3-pT3とBub1媒介のH2A-S121のリン酸化が協力して,CPCを内心センターメールに標的にすることを実証しました.
- H3-pT3が,生き残った細胞が核細胞に結合することを促進することを示した.
- H2A-S121のリン酸化がシュゴシン結合を促進することを明らかにした.
- HaspinがPds5経由でコヘシンとコロカライズし,Bub1がキネトコアでローカライズすることを発見した.
結論:
- 内セントロメアは,2つの異なるヒストンキナーゼ活性:ハスピンとBub1.1.の交差点によって定義されます.
- この二重キナーゼメカニズムは,CPCの内部セントロメアへの正確な徴募を保証し,これは忠実な染色体分割に不可欠です.
- この発見は,セントロメア組織とミトスの調節に関する新しい理解を提供します.
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