培養ドロソフィラ細胞のウルトラビトラックスタンパク質による転写活性化および抑制
M A Krasnow1, E E Saffman, K Kornfeld
1Department of Biochemistry, Stanford University, CA 94305.
Cell
|June 16, 1989
まとめ
ドロソフィラ・メラノガスターのオルトラビトラクス (Ubx) とアンテナペディア (Antp) のホメオティック遺伝子は遺伝子発現を制御する. Ubxタンパク質は,プロモーターの特定のDNA配列に結合することによって,転写活性化剤および抑制剤として機能します.
科学分野:
- 発達生物学 発達生物学とは
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
背景:
- ウルトラビトラックス (Ubx) やアンテナペディア (Antp) などのホメオティック遺伝子は,ドロソフィラ発達の過程でメタアメリカンアイデンティティを確立するために極めて重要です.
- これらの遺伝子は,下流の標的遺伝子の発現を調節することによって,その機能を果たすと考えられています.
研究 の 目的:
- 遺伝子プロモーターに対するUbxタンパク質の直接的な規制活動を調査する.
- 細胞アッセイにおける転写活性化剤および抑制剤としてのUbxタンパク質の予測された役割を確認する.
主な方法:
- 培養ドロソフィラ・メラノガスター細胞でコトランスフェクションアッセイを用いた.
- UbxとAntp遺伝子の融合プロモーター領域は,レポーター構造を構成し,規制活動を評価する.
- トランスクリプトレベルに対するUbxタンパク質の影響を分析し,特定の結合部位を特定しました.
主要な成果:
- Ubxタンパク質がアンテナペディア (Antp) プロモーター融合を抑制し,Ubxプロモーター融合を活性化することが示された.
- Ubxタンパク質は,正確に開始されたAntp P1とUbxトランスクリプトのレベルを調節することを確認しました.
- Ubxプロモーター活性化に不可欠なUbx結合部位のダウンストリームクラスターを特定し,これらの配列が異質プロモーターに規制を与えることを示しました.
結論:
- Ubxタンパク質は,転写抑制剤と活性化剤の両方として作用します.
- Ubxタンパク質の調節機能は,プロモーター領域内の配列に直接結合することによって媒介されます.
- Ubxタンパク質ファミリーは,潜在的に変異した形態のモジュラー設計で,同様の規制能力を発揮しています.
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