Gタンパク質のシグナル伝達は,タブ型タンパク質を通して行われます
S Santagata1, T J Boggon, C L Baird
1Ruttenberg Cancer Center, Structural Biology Program, Department of Physiology and Biophysics, Mount Sinai School of Medicine of New York University, 1425 Madison Avenue New York, NY 10029, USA.
Science (New York, N.Y.)
|May 26, 2001
まとめ
トビのタンパク質の機能障害は肥満を引き起こします. Tubbyは,膜に結合した転写レギュレータとして作用し,Gタンパク質シグナル伝達の後,核に移動し,信号伝達と遺伝子発現をリンクします.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- トビータンパク質機能障害は,マウスの肥満と関連しています.
- 転写調節体としてのtubbyの機能の正確な分子機構は完全に理解されていません.
研究 の 目的:
- 信号伝達におけるタビのタンパク質機能の分子機構を解明する.
- Gタンパク質結合受容体シグナル伝達経路におけるtubbyの役割を調査する.
主な方法:
- X線結晶学を用いて,タビータンパク質の局所化と,フォスファディチリノシトール4,5-ビスホスファートとの相互作用を調査した.
- Gタンパク質alphaq (Galphaq) アクティベーションとフォスフォリファーズC-βがチュービー転位に及ぼす効果を調べました.
- 管状タンパク質3 (TULP3) の局所化の調節を研究した.
主要な成果:
- Tubbyは,フォスファディチルノシトール4,5-ビスホスファートをtubbyドメイン経由でプラズマ膜に結合する.
- Galphaqの活性化は,膜からtubbyを放出し,核転位を誘発する.
- Tubbyドメインは,リン酸化ホスファティディルイノシトール結合因子として作用する.
- TULP3の局所化は,tubby.に類似して規制されています.
結論:
- Tubbyタンパク質は,膜に結合した転写レギュレータとして機能する.
- tubbyの核転位は,Gタンパク質のシグナル伝達と遺伝子発現の調節を結びつける,フォスフォニノシチドの水解によって誘発されます.
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