HMGのようなタンパク質で,転写活性化剤を抑制剤に切り替えることができる
N Lehming1, D Thanos, J M Brickman
1Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, Massachusetts 02138.
Nature
|September 8, 1994
まとめ
ドロソフィラ・DSP1タンパク質は,転写因子DorsalとNF-kappa Bを活性化因子から抑制因子に変換する. このスイッチは,HMGタンパク質を強調する負の規制要素に依存しています.
科学分野:
- 分子生物学は分子生物学である.
- 発達生物学 発達生物学とは
- 遺伝学 遺伝学とは
背景:
- 転写調節には,遺伝子発現を活性化または抑制できるタンパク質が含まれます.
- Relファミリーのメンバーであるドロソフィラタンパク質Dorsalは,初期の胚でtwistを活性化し,zenを抑制します.
- 転写活動の調節におけるHMGタンパク質の役割は完全に理解されていません.
研究 の 目的:
- ドロソフィラのHMG1タンパク質を特定し,特徴づけ,ドロサルの機能を調節する.
- HMGタンパク質が遺伝子活性化および抑制に影響を与えるメカニズムを調査する.
- HMGタンパク質が転写レギュレータを活性化モードと抑制モードに切り替えることができるかどうかを判断する.
主な方法:
- 新しいドロソフィラHMG1タンパク質,DSP1.1の識別とクローニング.
- 遺伝子発現アッセイにおけるドーサルおよびNF-カッパB活性に対するDSP1の効果の分析.
- DSP1媒介による抑圧に関与するネガティブな規制要素 (NRE) の識別と特徴付け.
主要な成果:
- 新しいドロソフィラHMG1タンパク質であるDSP1が特定されました.
- DSP1は,トランスクリプションアクティベータードーサルを抑制器に変換する.
- この抑制は,背中結合部位の近くにある負の規制要素 (NRE) に依存しています.
結論:
- DSP1はスイッチとして作用し,DorsalとNF-kappa Bを転写活性化剤から抑制剤に変換する.
- ネガティブな規制要素 (NRE) との相互作用は,このスイッチにとって極めて重要です.
- DSP1やHMG I(YなどのHMGのようなタンパク質は,規制タンパク質の転写結果を決定する上で重要な役割を果たします.
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