CREBのコアクティベーターであるTORC2は,カルシウムとcAMPに敏感な偶然検出器として機能します
Robert A Screaton1, Michael D Conkright, Yoshiko Katoh
1Peptide Biology Laboratories, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
Cell
|September 30, 2004
まとめ
栄養素と腸内ホルモンは,CREBを活性化することによって,臓の小島細胞機能を高めます. カルシヌーリンとSIK2を含む新しいシグナル伝達モジュールは,CREBの共同活性化剤であるTORC2を制御し,これらの経路を遺伝子発現に結びつける.
科学分野:
- 細胞の信号伝達経路は,
- エンドクリノロジー エンドクリノロジー
- 分子生物学は分子生物学である.
背景:
- 臓の小島細胞の活性は,グルコースと腸内ホルモンによって促進されます.
- カルシウムとcAMPの信号伝達経路は,転写因子CREBを活性化する.
研究 の 目的:
- 遺伝子の発現にカルシウムとcAMPの相乗効果を媒介するシグナル伝達モジュールの解明.
- 栄養素とホルモンシグナル伝達におけるCREBの共同活性化剤であるTORC2の役割を特定する.
主な方法:
- カルシネウリン,SIK2,およびTORC2.2の相互作用を調査しました.
- 14-3-3タンパク質とTORC2のリン酸化依存相互作用を分析した.
- カルシウムとcAMPがTORC2の脱リン酸化と核への侵入に及ぼす影響を調べました.
主要な成果:
- カルシネウリンとSIK2を含むシグナリングモジュールは,カルシウムとcAMP経路をTORC2.2に接続します.
- カルシウムはカルシヌーリンの活性性を高め,TORC2の脱リン酸化を促進する.
- cAMPはSIK2キナーゼの活性を抑制し,TORC2の脱リン酸化と核への侵入にもつながります.
結論:
- フォスファターゼ/キナーゼモジュールは,栄養素とホルモンのシグナルをCREBの共活性化剤TORC2.2とリンクする.
- このモジュールは,臓の小島細胞の遺伝子発現を調節する.
- TORC2:14-3-3複合体の破壊は,栄養素刺激によるシグナル伝達の鍵となる.
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