MAPK Hog1はRpd3ヒストン脱酸化酵素を募集し,オスマレスポンシブ遺伝子を活性化させます
Eulàlia De Nadal1, Meritxell Zapater, Paula M Alepuz
1Cell Signaling Unit, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, E-08003 Barcelona, Spain.
Nature
|January 23, 2004
まとめ
ミトゲン活性化タンパク質キナーゼ (MAPK) Hog1は,Rpd3-Sin3ヒストン脱セチラゼ複合体をオスモレスポンシブ遺伝子プロモーターに勧誘する. このターゲティングは,遺伝子発現を誘導することによって,高オスモラリティのストレス下での酵母細胞生存に不可欠です.
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:
- ミトゲン活性化タンパク質キナーゼ (MAPK) は,細胞適応のための遺伝子発現を調節する.
- MAPK Hog1は酵母における高オスモラリティによって活性化され,生存反応を調整する.
- Hog1の役割を含むMAPK媒介の遺伝子調節のメカニズムは完全に理解されていません.
研究 の 目的:
- MAPK Hog1がオスモストレスの反応として遺伝子発現を誘発するメカニズムを調査する.
- ヒストン脱エチラゼ複合体がHog1媒介の遺伝子調節に関与しているかどうかを判断する.
主な方法:
- 酵母遺伝学では,RPd3-Sin3複合体を欠くオスモスセンシティブ変異体を研究する.
- Hog1とRpd3.3との相互作用に関するインビボとインビトロの研究.
- 遺伝子プロモーターへのRpd3-Sin3複合体の結合を評価するためのクロマチンの免疫降水.
主要な成果:
- Rpd3-Sin3ヒストン脱酸化塩素複合体がない細胞は,高オスモラリティに敏感であり,オスモストレスの遺伝子発現が低下しています.
- Hog1はRPd3.3と物理的に相互作用する.
- Hog1は,Rpd3-Sin3複合体を,ストレスを受けたときに特定のオスモストレスの反応性遺伝子プロモーターに標的とし,ヒストンの脱エチル化,RNAポリメラーゼIIの募集,および遺伝子誘導につながる.
結論:
- MAPK Hog1によるRpd3ヒストン脱酸化酵素複合体のオスモレスポンシブプロモーターへのターゲティングは,オスモストレスの間に遺伝子発現を誘発するために不可欠です.
- このメカニズムは,オスモティックストレス下での酵母細胞の生存に不可欠です.
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