ヒストンH3ライシン36のコトランスクリプションセット2メチル化により,抑圧的なRpd3複合体が生成される
Michael-Christopher Keogh1, Siavash K Kurdistani, Stephanie A Morris
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Cell
|November 16, 2005
まとめ
酵母Rpd3ヒストン脱酸化酵素は,2つの複合体で機能する. Rpd3C(S) 複合体は,サブユニットRco1とEaf3で,Set2媒介ヒストンのメチル化により,転写されたDNAを脱エチル化し,遺伝子発現を調節するために採用されます.
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
- イースト遺伝学 イースト遺伝学
背景:
- 酵母ヒストン脱酸化酵素Rpd3 (タンパク質3を含むRPelA領域) は,プロモーターの転写開始を抑制する上で重要な役割を果たします.
- Rpd3は,異なるタンパク質複合体内で機能し,その調節作用に影響を与えます.
研究 の 目的:
- イーストの2つの異なるRpd3-を含む複合体の構成と機能を明らかにする.
- 転写された領域にRpd3C(S) が採用されるメカニズムと,遺伝子調節におけるその役割を調査する.
主な方法:
- Rpd3複合成分を特定するための生化学分析.
- ミュータントフェノタイプを評価するための遺伝子研究.
- 転写変化を測定するための遺伝子発現プロファイリング.
- タンパク質とDNAの相互作用を決定するためのクロマチン免疫降水 (ChIP).
- ヒストンのメチル化分析.
主要な成果:
- Rpd3は,Rpd3C(S) (小) とRpd3C(L) (大) の2つの複合体として存在する.
- Rpd3C(S) は,ユニークなサブユニットRco1とEaf3を含み,その変異体はSet2変異体と同様の表型を示しています.
- Eaf3染色体は,Rpd3C(SをH3K36メチル化核細胞に誘導し,転写された領域の脱エチル化を促進する.
- Set2またはRpd3C(S) 遺伝子の削除は,Bur1/Bur2.2の陽性延長因子の必要性を回避する.
結論:
- Rpd3C(S) 複合体は,Set2媒介ヒストンH3ライシン36メチル化により,積極的に転写される遺伝子に採用されます.
- この募集は,転写された領域の脱アセチル化につながり,転写の負の規制機構として作用します.
- Set2-Rpd3C(S) 経路は,酵母における適切な転写延長制御に不可欠である.
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The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
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