Tiki1は,Wntの裂け方-酸化と無活性化による頭部形成に必要である
Xinjun Zhang1, Jose Garcia Abreu, Chika Yokota
1The F. M. Kirby Neurobiology Center, Boston Children's Hospital, Department of Neurology, Harvard Medical School, Boston, MA 02115, USA.
Cell
|June 26, 2012
まとめ
研究者らは,頭形成に不可欠なWnt固有のプロテアゼであるTiki1を発見した. Tiki1は,Wntタンパク質を分裂させ,受容体結合を防止し,胚の発達を制御することによって,Wnt信号伝達を無効化する.
科学分野:
- 発達生物学 発達生物学について
- 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:
- 分泌されるWntモルフォゲンは,胚形成,再生,および病気のための重要なシグナル伝達分子です.
- Wntタンパク質は,その機能のために特定の翻訳後の修正を必要とします.
- 発達中のWntタンパク質の無活性化のメカニズムは,依然としてほとんど不明です.
研究 の 目的:
- 開発初期にWntシグナル伝達の新たなレギュレータを特定する.
- Wntタンパク質の無活性化のための潜在的なメカニズムを調査する.
- Xenopusの胚形成と前頭部の発達におけるTiki1の役割を理解するために.
主な方法:
- Xenopus胚における機能的なcDNAスクリーニング.
- 背面のスペマン・マンゴールド・オーガナイザーのTiki1の表情分析.
- Wntタンパク質の分裂とオリゴメリゼーションを評価するためのインビトロアッセイ.
- 人間の細胞におけるWnt機能の分析.
主要な成果:
- トランスメブランタンパク質であるTiki1は,Xenopus. inの前頭部発達に不可欠であると特定されました.
- Tiki1はWnt固有のプロテアゼとして作用し,Wntタンパク質のアミノ端末残基を分解する.
- この分裂は,受容体結合能力が低下した酸化されたWntオリゴーマーを生成します.
- Tiki1は,胚性およびヒト細胞の両方の文脈でWnt機能を逆らいます.
結論:
- Tiki1はタンパク質分解を通じてWntの無活性化を媒介し,酸化とオリゴメリゼーションにつながります.
- このメカニズムは,胚の発達中の頭形成を制御する.
- Wntアミノ端末は,この不活性化経路を回避する役割を果たします.
- Tiki1は,Wnt信号伝達の調節のための潜在的な治療目標を表しています.
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