細胞型特異のTATA結合タンパク質,TRFの転写特性
S K Hansen1, S Takada, R H Jacobson
1Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley 94720-3204, USA.
Cell
|October 23, 1997
まとめ
研究者らは,特定の細胞タイプにおける遺伝子転写を指揮するTATA結合タンパク質関連因子 (TRF) を発見した. この因子は,一般的なTATA結合タンパク質 (TBP) と異なり,組織および遺伝子特異の転写に役割を果たします.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 細胞生物学 細胞生物学
背景:
- ユカリオットの転写開始は,RNAポリメラーゼII.を勧誘するためにTATA結合タンパク質 (TBP) に依存しています.
- 細胞タイプ特異的な遺伝子調節の正確なメカニズムは完全に理解されていません.
研究 の 目的:
- ユカリオットの転写に関与する新しい要因を特定し,特徴づけること.
- 細胞タイプ特異的な遺伝子発現におけるTBP関連因子 (TRFs) の役割を調査する.
主な方法:
- 浄化された再結合タンパク質を用いたインビトロ転写アッセイ.
- 異なる遺伝子活性化を評価するために,細胞系でのトランスフェクション研究.
- 胚とポリテンの染色体に対する抗体染色,発現分析.
- TRF変異体における変異フェノタイプ (シェイカー/不妊男性) の分析.
主要な成果:
- 新しいTBP関連因子 (TRF) が特定され,TATA DNAの転写因子IIAおよびIIBと安定した複合体を形成しています.
- TRFは,RNAポリメラーゼIIの転写をインビトロで指向する際にTBPを代用することができます.
- TRFは,増強タンパク質による差異的活性化を示し,遺伝子選択的性質を示しています.
- TRFは,細胞型特異的な方法で発現され,発現パターンは観察された変異性フェノタイプと相関しています.
結論:
- TRFはTBPの機能的な同型であり,組織および遺伝子特異的な転写を指揮する.
- TRFは,文脈に依存した方法で遺伝子発現を調節する上で重要な役割を果たします.
- TRFの発見は,真核細胞の転写調節の複雑さについての新しい洞察を提供します.
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