ドロソフィラ Ubxとabd-Aタンパク質による遺伝子活性化とDNA結合
M L Samson1, L Jackson-Grusby, R Brent
1Department of Molecular Biology, Massachusetts General Hospital, Boston 02114.
Cell
|June 16, 1989
まとめ
Ubxとabd-Aタンパク質は,ドロソフィラの発達に不可欠である. 彼らのホメオドメインはDNAの結合に不可欠ですが,DNAの結合が他のタンパク質によって促進される場合,二分化,核への入り込み,または活性化には欠かせません.
科学分野:
- 発達生物学 発達生物学について
- 分子遺伝学 分子遺伝学
- ドロソフィラ・メラノガスターの研究
背景:
- Ubxとabd-A遺伝子の産物は,ドロソフィラの胸部と腹部構造の適切な発達に不可欠です.
- これらの転写因子の正確な分子機構を理解することは,発達経路の解読の鍵です.
研究 の 目的:
- Ubxおよびabd-Aタンパク質におけるホメオドメインのDNA結合と遺伝子活性化に関する機能的役割を調査する.
- Ubxとabd-A.によって媒介される二分化,核局所化,および転写調節に関する要件を解明する.
主な方法:
- 酵母におけるLexA-UbxとLexA-abdA融合タンパク質の発現.
- 遺伝子活性化を評価するために,LexAオペレーターまたはUbx結合部位を持つ標的遺伝子を利用する.
- ホメオドメインの機能を解剖するために,突然変異した融合タンパク質を使用します.
主要な成果:
- LexA-UbxとLexA-abdA融合タンパク質が標的遺伝子発現を活性化しました.
- ホメオドメインは,タンパク質の二重化や核の侵入に不可欠ではありませんでした.
- ホメオドメインは,DNA結合がLexA部分によって媒介されたとき,遺伝子の活性化には欠かせませんでした.
- ホメオドメインはUbxサイトに結合するために必要ですが,そのDNAの相互作用は,細菌のヘリックス-ターン-ヘリックスタンパク質とは異なります.
結論:
- ホメオドメインは,Ubxとabd-Aが特定のDNA部位に結合するのに不可欠です.
- Ubxとabd-Aによる遺伝子活性化は,主にDNA結合によって引き起こされます.
- これらのタンパク質によるネガティブな遺伝子調節は,おそらく他のドロソフィラの遺伝子産物との相互作用を含む.
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