TFIIHはRNAポリメラーゼIの転写に不可欠な役割を果たしています
Sebastian Iben1, Herbert Tschochner, Mirko Bier
1Division of Molecular Biology of the Cell II, German Cancer Research Center, D-69120, Heidelberg, Germany.
Cell
|May 23, 2002
まとめ
転写因子IIH (TFIIH) 複合体は,リボソームのRNA合成に不可欠である. この研究は,TFIIHを明らかにしています.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子発現の表現について
- DNA修復 DNA修復する
背景:
- 転写因子II H (TFIIH) は,DNA修復とタンパク質をコードする遺伝子転写に関与する重要なタンパク質複合体です.
- リボソームのRNA (rRNA) 合成におけるその役割は,以前は確立されていなかった.
研究 の 目的:
- リボソームRNA合成におけるTFIIHの役割を調査する.
- RNAポリメラーゼIの転写にTFIIHが必要かどうかを判断する.
主な方法:
- TFIIH.の温度感受性変異を持つ酵母菌株を使用した.
- マウスの細胞分子を用いた in vitro トランスクリプションアッセイを実施した.
- 核細胞内のTFIIHの局所化とそのRNAポリメラーゼIおよびTIF-IBとの関連を調査した.
主要な成果:
- 酵母TFIIH変異株では,pre-rRNA合成が損なわれていました.
- TFIIHは核olusに局所化し,マウス細胞のRNAポリメラーゼIおよびTIF-IBと結合することが判明しました.
- TFIIHが欠けていたトランスクリプションシステムは不活性になり,TFIIHを追加すると活性が回復した.
- TFIIHは,rDNA転写の生産性 (中絶性ではない) に必要であり,開始後の機能を示している.
結論:
- TFIIHは,体内および体外でのリボソームRNA合成に不可欠です.
- TFIIHは,RNAポリメラーゼI転写の開始後の役割を果たしています.
- この研究は,rRNA遺伝子転写と転写結合修復の間の分子リンクを確立しています.
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