TRF1:BRF複合体は,ドロソフィラのRNAポリメラーゼIIIの転写を指揮する
1Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, 94720, USA.
Cell
|June 13, 2000
まとめ
ドロソフィラでは,TBPではなくBRFと複合したTATA結合タンパク質関連因子1 (TRF1) が,RNAポリメラーゼIIIの転写を媒介する. この発見は,トランスクリプションにおけるTBPの普遍的な役割に挑戦しています.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- バイオケミストリー バイオケミストリー
背景:
- TATA結合タンパク質 (TBP) は,伝統的にRNAポリメラーゼI,II,IIIの普遍的な転写因子と考えられています.
- ドロソフィラにおけるRNAポリメラーゼIII (Pol III) の転写開始の正確なメカニズムは完全に解明されていません.
研究 の 目的:
- ドロソフィラのRNAポリメラーゼIII転写におけるTBP関連因子の役割を調査する.
- このモデル生物におけるPol IIIの転写に責任を負う特定のタンパク質複合体を特定する.
主な方法:
- 免疫プレシピテーションは,タンパク質の相互作用を特定するための測定法です.
- 免疫欠乏した抽出物と再結合タンパク質を用いた in vitro 転写アッセイ.
- ポリテン染色体の部位におけるタンパク質のコロカライゼーションの分析 in vivo 方法を用いて.
主要な成果:
- TBPではなくTBP関連因子1 (TRF1) は,ドロソフィラのRNAポリメラーゼIII転写に不可欠である.
- TRF1とBRFの複合体は,tRNA,5S,U6RNA遺伝子の転写を再構成するために必要です.
- TRF1とBRFは,主としてin vivoで複合され,ポリテン染色体上のPol III遺伝子ロシでコロカライズすることが判明しました.
結論:
- TRF1はBRFとの複合体で,ドロソフィラのRNAポリメラーゼIII転写に重要な役割を果たし,TBPの一般に認められた役割を置き換えています.
- この研究は,ドロソフィラのPol III転写開始に関与する要因を再定義し,TRF1.1の重要性を強調しています.
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