ドロソフィラのハンクバックとクルーペルによってコードされたギャップタンパク質の配列特異的なDNA結合活動
D Stanojević1, T Hoey, M Levine
1Department of Biological Sciences, Fairchild Center, Columbia University, New York, New York 10027.
Nature
|September 28, 1989
まとめ
ドロソフィラのギャップ遺伝子であるハンクバック (hb) とクルーペル (Kr) タンパク質はDNAを結合し,遺伝子転写を調節する. それらは特定のDNA配列と相互作用し,初期の胚発達と遺伝子発現パターンを制御します.
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:
- ドロソフィラの体平面のセグメンテーションは,規制遺伝子に依存しています.
- ハンクバック (hb) とクルーペル (Kr) のようなギャップ遺伝子は,このプロセスにとって極めて重要です.
- hbおよびKrタンパク質のDNA結合メカニズムは以前は知られていなかった.
研究 の 目的:
- ハンクバック (hb) とクルーペル (Kr) タンパク質のDNA結合活動を調査する.
- hbとKr.によって認識された特定のDNA配列を特定するために.
- ドロソフィラの発達初期における遺伝子発現の調節におけるhbとKrの役割を調査する.
主な方法:
- hbおよびKrタンパク質のDNA結合活動の分析.
- hb と Kr. のコンセンサスDNA結合モチーフの識別
- 均等にスキップされた (eve) プロモーターとのhbとKrの相互作用の調査.
主要な成果:
- hbとKrの両方のタンパク質は,配列特異的なDNA結合活性を示しています.
- hb結合部位は,コンセンサスモチーフを共有しています: G/A C/C ATAAAAAAAA.
- Krの結合部位は,明確なモチーフを共有しています: AACGGGTTAA.AAC.
- 証拠によると,hbとKrのタンパク質は協力して遺伝子発現を調節する.
- hb と Kr は特定のエブプロモーター要素と相互作用し,その周期性に影響を与えます.
結論:
- ハンクバック (hb) とクルーペル (Kr) タンパク質は,ドロソフィラの発達初期に転写調節体として機能する.
- 配列特異的なDNA結合は,遺伝子発現パターンを制御するために不可欠です.
- イーブ (eve) のような標的遺伝子プロモーターとの協同結合と相互作用は,ボディプランのセグメンテーションにおける重要なメカニズムである.
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