エピジェネティックTRIMによるレトロウイルスサイレンシング
James Ellis1, Akitsu Hotta, Mojgan Rastegar
1Developmental and Stem Cell Biology Program, SickKids Hospital, Toronto, Ontario, Canada. jellis@sickkids.ca
Cell
|October 10, 2007
まとめ
胚細胞は,TRIM28コアプレッサー複合体を用いてレトロウイルスDNAを認識し,その複合体はウイルスのプライマー結合部位と結合します. この結合は,ヒストンの改変とヘテロクロマチンのタンパク質結合を通じた転写のエピジェネティックサイレンシングを開始する.
科学分野:
- 分子生物学は分子生物学である.
- エピジェネティクス エピジェネティクス
- ウイルス学 ウイルス学 ウイルス学
背景:
- 胚細胞は,レトロウイルスからの転写を沈黙させるメカニズムを持っています.
- ウイルスのDNAを認識するための正確な分子シグナルは,まだ完全に理解されていません.
研究 の 目的:
- 胚細胞がレトロウイルスDNAを認識し,沈黙させるメカニズムを解明する.
- このプロセスに関与する特定のタンパク質複合体と表遺伝子マークを特定する.
主な方法:
- クロマチンの免疫プレシピテーション測定は,タンパク質の結合部位を特定するために行われます.
- エピジェネティックマークを検出するためのヒストンの改変分析.
- TRIM28コアプレッサー複合体とHP1ガンマ相互作用に関する研究.
主要な成果:
- TRIM28コアプレッサー複合体は,レトロウイルスプライマー結合部位と結合することが判明しました.
- エピジェネティックサイレンシングは,ヒストンH3 (H3K9me2) のライシン9にディメチルマークを積むことを含む.
- ヘテロクロマチンタンパク質HP1gammaは,H3K9me2マークの重要な読者として特定され,転写サイレンシングを媒介しました.
結論:
- TRIM28は,胚細胞におけるレトロウイルスDNAの重要な認識因子として機能する.
- H3K9me2とHP1gammaを含む特定の表遺伝経路は,レトロウイルス転写の静止を媒介する.
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