Ultrabithoraxのタンパク質は,それ自身とAntennapedia P1プロモーターに近い配列を結合する
P A Beachy1, M A Krasnow, E R Gavis
1Department of Biochemistry, Stanford University School of Medicine, California 94305.
Cell
|December 23, 1988
まとめ
フルーツフライの発達に不可欠なUltrabithorax (Ubx) タンパク質は,自身の近くにあるDNA配列とAntp (アンテナペディア) 遺伝子プロモーターを直接結合する. この結合は,Ubxが特定のDNA領域と相互作用することで,遺伝子活動を調節することを示唆しています.
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:
- ドロソフィラのUltrabithorax (Ubx) 遺伝子は,セグメントアイデンティティを制御するタンパク質をコードする.
- Ubxタンパク質は,後部胸部と前部腹部セグメントの発達運命を指定する上で重要な役割を果たします.
- 遺伝子研究によると,Ubxはアンテナペディア (Antp) ホメオティック遺伝子を抑制する.
研究 の 目的:
- Ubxタンパク質が遺伝子発現を調節する分子機構を調査する.
- Ubxタンパク質がDNA結合タンパク質であるかどうかを判断し,そのDNA標的を特定する.
- Ubxタンパク質と標的遺伝子の規制領域の間の直接的な相互作用を解明する.
主な方法:
- 過剰生産するEscherichia coli菌株からのUbxタンパク質ファミリーの成分の浄化.
- 精製されたUbxタンパク質を配列特異的なDNA結合タンパク質として特徴づける.
- Ubxタンパク質に結合するDNA配列の識別と分析,UbxとAntpプロモーターの近くの配列を含む.
主要な成果:
- Ubxタンパク質のメンバーがE. coliから成功裏に浄化されました.
- 浄化されたUbxタンパク質は,配列特異的なDNA結合活性を示した.
- 結合部位は,Ubx遺伝子のプロモーターとAntp P1プロモーターの近くで特定されました.
- これらの結合部位は40から90bpの範囲で,TAAまたはTAA-TCGのタンデムリピートを含んでいます.
結論:
- Ubxタンパク質は,配列特異のDNA結合を通じて遺伝子発現を直接制御する.
- 特定された結合部位は,Ubx媒介の転写調節のための直接的なメカニズムを示唆しています.
- これらの発見は,発達パターニングにおけるUbxの役割についての分子洞察を提供します.
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