梯度形質バイコイドは,濃度依存の転写活性化剤である
G Struhl1, K Struhl, P M Macdonald
1Howard Hughes Medical Institute, Columbia University College of Physicians and Surgeons, New York, New York 10032.
Cell
|June 30, 1989
まとめ
ビコイド (bcd) タンパク質のグラデーションは,ドロソフィラ胚におけるハンクバック (hb) 遺伝子の活性化を制御する. 複数のhb遺伝子要素がbcd濃度に反応し,正確な遺伝子発現パターンを決定する.
科学分野:
- 発達生物学 発達生物学について
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
背景:
- ビコイド (bcd) タンパク質は,初期のドロソフィラ胚で前後部グラデーションを形成する.
- bcdは,特定の前面ドメインのセグメンテーション遺伝子ハンクバック (hb) のジゴティック活性化を調節する.
研究 の 目的:
- ハンクバック (hb) 遺伝子がビコイド (bcd) タンパク質グラデントにどのように反応するかを調査する.
- bcd依存転写を媒介する複数の規制要素の役割を決定する.
- bcdとhbの遺伝子調節の間の濃度依存の相互作用を探求する.
主な方法:
- hb遺伝子内の規制要素の分析.
- ドロソフィラ胚におけるイン・ビボ発現パターンの研究.
- イーストにおけるインビトロ転写活性化アッセイ.
主要な成果:
- hb遺伝子は,bcdタンパク質によって活性化される複数の調節要素を有しています.
- 表現パターンは,bcd グラデーションプロファイルと hb 要素の特徴に決定的に依存しています.
- bcd依存のhb元素の活性化は酵母体で発生し,特定のbcdタンパク質ドメインを必要とします.
結論:
- bcdタンパク質は,濃度に依存した方法でhb遺伝子を結合し活性化します.
- bcdグラディエントはhb遺伝子の活性化を指示し,前側の発現境界を定義します.
- このメカニズムはおそらく他の遺伝子にも広がり,BCDは結合親和性に基づいて従属遺伝子を活性化します.
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