Wnt3a媒介によるフォスファディチリノシトール4,5-ビスホスファートの形成は,LRP6のリン酸化を調節する
Weijun Pan1, Sun-Cheol Choi, He Wang
1Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06510, USA.
まとめ
フォスファディチルイノシトール-4-リン酸5キナーゼタイプI (PIP5KI) は,Wnt信号伝送に不可欠です. Wnt3aは,Phosphatidylinositol 4,5-bisphosphates [PtdIns (4,5) P2]を生成するPIP5KIを活性化させ,低密度リポプロテイン受容体関連タンパク質6 (LRP6) のリン酸化を調節する.
科学分野:
- 細胞の信号伝達経路は,
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- Wnt-β-catenin経路は,細胞プロセスにおいて根本的な役割を果たしています.
- 活性化には,Wnt受容体,低密度リポプロテイン受容体関連タンパク質6 (LRP6) のリン酸化が必要です.
- 特定のリン酸化部位 (Thr1479とSer1490) は,経路の開始に不可欠である.
研究 の 目的:
- Wnt誘発のLRP6リン酸化に関与するキナーゼを特定する.
- Wnt信号がLRP6リン酸化を調節するメカニズムを解明する.
- Wnt信号伝達における特定されたキナーゼの役割を確認する.
主な方法:
- ヒトキナーゼのスクリーニング 小型の干渉RNAライブラリ.
- 哺乳類の細胞におけるThr1479およびSer1490におけるLRP6リン酸化の評価.
- キナーゼの重要性を確認するために,Xenopus胚における機能的研究.
主要な成果:
- フォスファディチルイノシトール4キナーゼタイプIIアルファとフォスファディチルイノシトール4フォスファート5キナーゼタイプI (PIP5KI) は,Wnt3a誘発のLRP6リン酸化に必須であるとして,Ser1490.
- Wnt3aシグナル伝達は,フォスファディチリノシトール4,5-ビスホスファート [PtdIns (4,5) P2]の生産を刺激する.
- Dishevelledは,PIP5KIと直接相互作用して活性化し,PtdIns (4,5) P2形成につながります.
- PtdIns (4,5) P2は,Thr1479とSer1490.2の両方でLRP6のリン酸化を調節する.
結論:
- Wnt媒介によるLRP6リン酸化のための新しいシグナリングメカニズムが明らかにされました.
- PIP5KIとその産物であるPtdIns (4,5) P2は,Wntシグナリングの開始の重要なレギュレーターである.
- この経路は,Wnt関連疾患に対する治療的介入の新たなターゲットを提供します.
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