ヘテロクロマチンとRNAiは,セントロメアにおけるCENP-Aクロマチンを確立するために必要です
Hernan Diego Folco1, Alison L Pidoux, Takeshi Urano
1Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, 6.34 Swann Building, Edinburgh EH9 3JR, Scotland, UK.
Science (New York, N.Y.)
|January 5, 2008
まとめ
RNA干渉 (RNAi) 誘導のヘテロクロマチンは,分裂酵母センターメアのCENP-Aクロマチンとキネトコアを組み立てるのに不可欠です. このヘテロクロマチンは最初の組み立てを導き,その後CENP-Aクロマチンは表遺伝的に維持されます.
科学分野:
- エピジェネティクス エピジェネティクス
- 分子生物学は分子生物学である.
- クロマチンの生物学
背景:
- ヒストンH3ライシン9メチル化 (H3K9me) によって標識されたヘテロクロマチンは,ヘテロクロマチンタンパク質1 (HP1) を採用し,キネトコア組立に不可欠なCENP-Aクロマチンの近くに存在します.
- セントロメリッククロマチンは,特にCENP-Aは,細胞分裂中の適切な染色体分離に不可欠です.
研究 の 目的:
- 分裂酵母センターメアのCENP-Aクロマチンとキネトコアの組み立てにおけるRNA干渉 (RNAi) 誘導ヘテロクロマチンの役割を調査する.
- セントロメリックヘテロクロマチンと,そのCENP-Aとの関係を確立し,維持するための重要な要因を特定する.
主な方法:
- 分裂酵母をモデル生物として利用した.
- H3K9メチルトランスフェラーゼClr4,リボヌクレアゼDicer,RNA誘発発転写遺伝子サイレンシング (RITS) コンポーネントChp1,Swi6 (HP1) を含む主要なタンパク質の機能を調査しました.
- CENP-A (((Cnp1) とナイヴ・セントロメリック・テンプレートでのキネトコア・アセンブリに対するこれらの要素の要求を検証した.
主要な成果:
- 中央キネトコア領域を横断するRNAi誘導ヘテロクロマチンは,CENP-A ((Cnp1) とキネトコア組立を促進するために不可欠であることを実証しました.
- Clr4,Dicer,Chp1,Swi6が,新しいセンターメリック配列のCENP-A(Cnp1) クロマチンを確立するために必要であることを示した.
- CENP-A(Cnp1) クロマチンが組み合わされると,ヘテロクロマチンとは独立してエピジェネティックに伝播されることが判明しました.
結論:
- セントロメリックRNAi誘導ヘテロクロマチンは,CENP-Aクロマチンとキネトコア組成の初期確立において重要な役割を果たします.
- この研究は,セントロメア同一性の表遺伝的調節におけるセントロメアRNAiの保存された役割を明らかにしています.
- この発見は,RNAiがセントロメリッククロマチンの表遺伝子遺伝を誘導する新しい機能を強調しています.
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Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
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