シリアのGタンパク質結合受容体Gpr161は,cAMPシグナル伝達を通じてSonic hedgehog経路を否定的に調節する
Saikat Mukhopadhyay1, Xiaohui Wen, Navneet Ratti
1Department of Research Oncology, Genentech Inc., South San Francisco, CA 94080, USA. saikat.mukhopadhyay@utsouthwestern.edu
Cell
|January 22, 2013
まとめ
G-タンパク質結合受容体Gpr161は,プライマリシリアにおけるソニック・ヘッジホッグ (Shh) 信号調節に不可欠である. その喪失により,SHH信号伝達が増加し,神経管の発達に影響を与えます.
科学分野:
- 細胞生物学 細胞生物学
- 発達生物学 発達生物学とは
- 分子生物学は分子生物学である.
背景:
- プライマリシリウムは,脊椎動物におけるソニック・ヘッジホッグ (Shh) 信号伝達に不可欠である.
- イントラフラゲラトランスポート複合体A (IFT-A) の変異は,逆説的にShhシグナリングを増加させる.
- IFT-Aは,タブのようなタンパク質であるTulp3をシリアに勧誘する.
研究 の 目的:
- プライマリーシリア内のShh信号調節に関与する新しい成分を特定する.
- Tulp3/IFT-A依存性シリアの局所化とShh経路の調節におけるGpr161の役割を調査する.
主な方法:
- Gpr161.1.の遺伝的喪失を有するマウスモデルを使用した.
- Tulp3とIFT-A.との関連で,Gpr161のプライマリシリアの局所化を分析した.
- Gpr161変異体におけるShh信号経路活性とGli3処理を評価した.
- 測定されたサイクルAMP (cAMP) レベルと,シリアからGpr161の内部化.
主要な成果:
- Gpr161は,Tulp3/IFT-Aに依存した方法で,一次性シリアに局所する.
- マウスの完全なGpr161喪失は妊娠中期の死亡率と神経管のShhシグナル伝達が上昇し,Tulp3/IFT-A変異体を模倣する.
- 活性Gpr161はcAMPを上昇させ,Gli3抑制剤の形態を促進することによってShh信号を抑制する.
- Shhシグナリングは,シリアからGpr161の内部化を誘導し,その活動を抑制します.
結論:
- Gpr161は,プライマリシリアにおけるShh信号の重要なレギュレータである.
- Gpr161は,神経管の発達に不可欠な,脊椎動物の保存されたGタンパク質結合受容体として機能する.
- Gpr161は,cAMP調節とGli3処理を介してShhシグナル伝達へのタンパク質キナーゼA活性化をリンクする経路を定義しています.
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