哺乳類のRNAポリメラーゼIIホロ酵素で,プロモーター特異の転写開始に必要なすべての成分を含んでいる

V Ossipow¹, J P Tassan, E A Nigg

¹Département de Biologie Moléculaire, Sciences II, Université de Genéve, Switzerland.

Cell

|October 6, 1995

まとめ

研究者は,哺乳類の細胞で完全なRNAポリメラーゼIIホロ酵素を特定し,真核生物とプロカリオットの転写開始の類似性を示唆しました. この複合体には,遺伝子発現に不可欠な重要な転写因子が含まれています.

科学分野:

分子生物学は分子生物学である.
バイオケミストリーバイオケミストリー
遺伝学遺伝学とは

背景:

タンパク質キナーゼMO15/CDK7は,転写因子TFIIHと関連しています.
MO15/CDK7はRNAポリメラーゼIIのカルボキシ末端ドメインをリン酸化する.

研究の目的:

MO15/CDK7とRNAポリメラーゼIIの転写機構との関連を調査する.
哺乳類の細胞におけるRNAポリメラーゼIIホロ酵素の成分を特定する.

主な方法:

抗MO15/CDK7抗体を用いたモノクローナル抗体の共免疫プレシピテーション.
ネズミの肝臓核抽出物の分析.

主要な成果:

MO15/CDK7抗体の共免疫発現したRNAポリメラーゼII,TFIID,TFIIB,TFIIH,TFIIF,TFIIE.
免疫プレシピテートには,HNF1,HNF4,C/EBPαなどの転写活性化タンパク質が欠けていた.
哺乳類の細胞でRNAポリメラーゼIIホロ酵素を自律的に誘発する証拠が見つかりました.

結論:

哺乳類の細胞には,RNAポリメラーゼIIホロ酵素が含まれており,自律的発酵が可能である.
この発見は,ユカリオットとプロカリオットのトランスクリプション開始の間の機能的パラレルを示唆しています.

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