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Elk-1マルチサイトリン酸化の相反効果は,ERK活性化に対する反応を形作る
Anastasia Mylona1, Francois-Xavier Theillet2, Charles Foster1
1Signalling and Transcription Laboratory, Francis Crick Institute, Lincoln's Inn Fields Laboratory, London WC2A 3LY, UK.
Science (New York, N.Y.)
|October 15, 2016
まとめ
ERKによるElk-1のマルチサイトリン酸化は,遺伝子活性化を制御する. いくつかのリン酸化部位は,メディエーター複合体の徴集を促進するが,他の部位は,エルク-1を制限する.
科学分野:
- 分子生物学
- 生物化学
- 遺伝子調節
背景:
- マルチサイトリン酸化は,エルク-1のような転写因子を調節するために不可欠です.
- タンパク質キナーゼERKは,エルク-1の転写活性化領域 (TAD) をリン酸化して遺伝子転写を強化する.
- Elk-1の個々のリン酸化部位の具体的な役割は不明でした.
研究 の 目的:
- Elk-1 TAD内の個々のリン酸化部位の異なる役割を明らかにする.
- Elk-1機能とメディエーター複合体の相互作用に差異性リン酸化率がどのように影響するかを理解する.
主な方法:
- 8つのTADサイトでリン酸化率を決定する時間解像度核磁気共鳴 (NMR) スペクトロスコーピー.
- 特定のリン酸化イベントの機能的影響を評価するためのサイト指向型変異.
主要な成果:
- ELK-1 TADのERK2リン酸化は,8つの特定された部位で異なる高速,中間,および遅い速度で発生しました.
- 素早い部位と中間部位の酸化により,メディエーターの相互作用と転写の活性化が強化された.
- 遅い部位のリン酸化は,メディエーター相互作用と転写活性化の両方を阻害し,ネガティブなフィードバックメカニズムとして作用した.
結論:
- ERKによるElk-1酸化は自己制限プロセスであり,特異的なサイトが転写出力を調節する.
- ERK活性化に対するElk-1の反応を微調整し,フォスファテーゼの活性から独立する.
- これは遺伝子転写の制御を正確に制御するための新しいメカニズムを提供します.
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