異なるβ-カタニンは,C. elegansの粘着とシグナル伝達機能を媒介する

H C Korswagen¹, M A Herman, H C Clevers

¹Department of Immunology, University Medical Center Utrecht, The Netherlands. R.Korswagen@lab.azu.nl

Nature

|August 22, 2000

まとめ

C. elegansでは,異なるβ-カテニンタンパク質がWntシグナル伝達と細胞結合を処理する. BAR-1は,Wnt経路の遺伝子活性化のためにPOP-1と提携し,HMP-2は粘着を媒介する.

科学分野:

分子生物学は分子生物学である.
発達生物学発達生物学について
遺伝学遺伝学とは

背景:

ベータ-カタニンタンパク質は,脊椎動物やハエのWnt信号伝達と細胞結合に不可欠です.
C. elegansでは,3つのβ-カタニン同種 (WRM-1,BAR-1,HMP-2) が存在し,WRM-1とPOP-1は以前にWnt信号伝達に関与していた.
C. elegansにおけるこれらの同類体の正確な役割と相互作用は不明のままである.

研究の目的:

Wnt信号伝達と細胞結合におけるC. elegansベータ-カタニン同類体の特異的な機能を明らかにする.
どのβ-カテニンの同類体がTcfの同類体POP-1と直接相互作用するかを決定する.
C. elegans.におけるWnt経路の活性化と遺伝子発現のメカニズムを明らかにする.

主な方法:

同免疫プレシピテーションアッセイは,β-カテニンの同類体とPOP-1との間のタンパク質相互作用をテストするアッセイです.
BAR-1/POP-1複合体の形成に対する反応として,遺伝子発現,特にホックス遺伝子 mab-5の分析.
HMP-2とC. elegansのカデリンHMR-1との相互作用を調査する.

主要な成果:

BAR-1は,POP-1と直接相互作用する唯一のβ-カテニンホモログとして特定されました.
BAR-1/POP-1複合体は二重転写因子として機能し,mab-5のようなWnt標的遺伝子を活性化します.
HMP-2は,C. elegansのカデリンHMR-1と相互作用する唯一のβ-カテニンホモログであることが判明しました.

結論:

カノニカルなWnt信号経路がC. elegans.で動作しています.
細胞粘着とWntシグナル伝達におけるβ-カタチニンの機能は,C. elegans.で異なるタンパク質に分離されている.
BAR-1はWntシグナル伝達を介し,HMP-2は細胞粘着を担当する.

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