ポリコンブ複合体であるPRC1によるクロマチン構造の安定化

Z Shao¹, F Raible, R Mollaaghababa

¹Department of Molecular Biology, Massachusetts General Hospital, Boston 02114, USA.

Cell

|July 21, 1999

まとめ

ポリコンブ抑制複合体1 (PRC1) は,遺伝子抑制を維持し,SWI/SNFリモデリング複合体と競合する. PRC1はヒストンの尾から独立して機能し,表遺伝的調節における明確なメカニズムを示唆する.

科学分野:

発達生物学発達生物学とは
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.

背景:

ポリコンブ群 (PcG) の遺伝子は,発達中のホメオティック遺伝子抑制を維持するために不可欠です.
SWI/SNFファミリーの変異は,PcG遺伝子変異によって引き起こされる欠陥を抑制することができます.

研究の目的:

ポリコンブ抑圧複合体1 (PRC1) を浄化し,特徴づけること.
PRC1とSWI/SNFリモデリング複合体の機能的関係を調査する.

主な方法:

PRC1複合体の浄化. PRC1複合体の浄化.
SWI/SNF媒介の核細胞配列改造に対するPRC1の効果をテストするアッセイ.
ヒストンの尾を持つ,または無する核群の配列を用いた実験.

主要な成果:

PRC1は精製され,いくつかのPcG遺伝子の産物を含んでいることが判明しました.
ヌクレオソーム配列によるPRC1のプレインキュベーションは,SWI/SNFリモデリングを阻害しました.
PRC1の再構築活動は,ヒストンの尾が欠けている核細胞配列で観察されました.

結論:

PRC1とSWI/SNFは,核群のテンプレートに競争するかもしれない.
尾のないヒストンに対するPRC1の活動は,ヒストンの尾の相互作用から独立したメカニズムを示唆し,これを deacetylasesのような他の抑圧的な複合体から区別する.

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