シルカディアンタンパク質BMAL1は,S6K1媒介によるリン酸化に反応して翻訳を調節する
Jonathan O Lipton1, Elizabeth D Yuan2, Lara M Boyle2
1Department of Neurology, Kirby Neurobiology Center, Children's Hospital, Boston, MA 02115, USA; Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA.
Cell
|May 19, 2015
まとめ
シルカディアン・タイム・システムは,タンパク質合成を調節する. BMAL1タンパク質は,昼夜リズムとmTORシグナリングをリンクし,翻訳を促進し,時計を拡張します.
科学分野:
- シルカディアン生物学
- 分子生物学は分子生物学である.
- セルラー・シグナリング
背景:
- サーカディアン・タイム・システムは,リズム・トランスクリプションを通じて細胞機能を同期します.
- サーカディアンシステムによるトランスレーションレベルでの遺伝子発現の調節は十分に理解されていません.
研究 の 目的:
- サーカディアンシステムが,トランスレーションレベルでの遺伝子発現をどのように調節するかを調査する.
- タンパク質合成におけるBMAL1の役割を決定する.
主な方法:
- 翻訳機構とBMAL1の関連性を調べました.
- S6K1のリン酸化がBMAL1の機能に与える影響を調べました.
- BMAL1活動に関連して測定されたタンパク質合成率.
主要な成果:
- BMAL1はサイトゾールの翻訳機構と関連し,タンパク質合成を促進します.
- リボソームS6タンパク質キナーゼ1 (S6K1) がリズム的にリン酸化するBMAL1.1.
- S6K1媒介によるリン酸化は,BMAL1の翻訳機構とタンパク質合成の刺激との関連に不可欠です.
- タンパク質合成の速度は,BMAL1.1に依存する昼間の振動を示しています.
結論:
- BMAL1は,昼間のトランスクリプションとトランスレーションにおいて二重の役割を果たします.
- BMAL1は昼間のタイミングをmTORシグナル伝達経路とリンクしている.
- 昼間の時計は,転写に加えてタンパク質合成を調節する.
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