誘発された子宮外シナトコア組立は,CENP-A核分子の要求を回避する
Karen E Gascoigne1, Kozo Takeuchi, Aussie Suzuki
1Whitehead Institute for Biomedical Research, Department of Biology, Nine Cambridge Center, MA 02142, USA.
Cell
|May 3, 2011
まとめ
2つの重要なタンパク質であるCENP-CとCENP-Tは,細胞分裂時に正確な染色体分離を保証する細胞構造であるキネトコアを構築するために不可欠です. 彼らのDNA結合ドメインは,CENP-Aから独立して,キネトコア組立を誘導する.
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:
- 正確な染色体分離は細胞分裂に不可欠であり,セントロメアで組み立てられたキネトコア複合体に依存しています.
- セントロメリックヒストンH3変種CENP-Aはセントロメアを特定することが知られていますが,ヒト細胞でキネトコアを完全に組み立てるには不十分です.
研究 の 目的:
- 構成的なDNA結合キネトコア成分CENP-CとCENP-Tがキネトコア形成を誘導する役割を調査する.
- CENP-CとCENP-TがCENP-Aとは独立してキネトコア組立を駆動できるかどうかを判断する.
- キネトコア組立におけるCENP-Tリン酸化などの規制メカニズムを探求する.
主な方法:
- 異なったDNA結合領域を持つCENP-CおよびCENP-Tタンパク質をエンジニアリングして,子宮外染色体位置をターゲットにします.
- KMN ネットワークと Mad2.2 を含む,キネトコア コンポーネントの組み立てを評価しました.
- 微小管の付着と,子宮外のシナトコアのような焦点の染色体分離を評価した.
- キネトコア組立に対するCENP-Tリン酸化の影響を調査した.
主要な成果:
- CENP-CとCENP-TのDNA結合ドメインを代替ターゲティングドメインに置き換えると,子宮の外部部部位でCENP-A独立のキネトコア組立が誘発された.
- これらの子宮外シナトコアは機能的であり,コンポーネントのステキオメトリックアセンブリ,マイクロチューブルの付着,およびMad2の徴募によって証明された.
- 焦点を含む染色体は適切な分離を示した.
- CENP-Tのリン酸化は,ミトーシス中の内生性および子宮外性キネトコア組成の両方の調節剤として特定されました.
結論:
- CENP-CとCENP-Tは,脊椎動物のキネトコア組立のための重要なプラットフォームとして機能します.
- これらのタンパク質は,DNA結合能力を通じて,他のキネトコア成分の採用を指示し,機能的なキネトコア形成を可能にします.
- CENP-Tリン酸化は,キネトコア組立の動態を制御するための規制機構を提供します.
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