分泌されるノギンタンパク質は,Xenopus mesodermのドーサライゼーションにおけるSpemannオーガナイザーを模倣する
1Department of Molecular and Cell Biology, University of California, Berkeley 94720.
Nature
|February 11, 1993
まとめ
スペーマンのオーガナイザーで発現するノギンタンパク質は, gastrulation 中のドルザライジング信号として作用します. アクティビンとは異なり,腹部組織における筋肉形成を誘発し,ノギンが鍵となるドーサライジング信号であることを示唆しています.
科学分野:
- 発達生物学 発達生物学とは
- 胚形成とは,胚の形成である.
- 分子シグナル伝達です.
背景:
- ガストルーレーションの間,スペーマンのオーガナイザーからのドルザライジング信号は,腹部 (血液,メゼンキーム) の代わりに,背面の宿命 (筋肉,心臓,プロネフロス) に向かって横側メソダーマ組織を指定します.
- アクティビンやフィブロブラスト成長因子などの既知のメソデーム誘発剤は,このドルサライゼーション効果を複製することはできません.
研究 の 目的:
- オーガナイザーで発現する遺伝子ノギンが,ドルザライジング信号として機能するかどうかを調査する.
- ノーギンタンパク質が,背中メソダーマの運命を誘発できるかどうかを判断する.
主な方法:
- 溶解性ノギンタンパク質を,胃流の際に腹側辺縁領域に添加する.
- ノギンへの反応としてメソダーマ組織の仕様の評価.
- ベントラライズされた胚の背面パターンの部分的な救出は,ナゴギンを発現させるためのプラズミド注射によって行われます.
主要な成果:
- 溶解性ノグギンタンパク質は,腹側辺縁領域の筋肉形成を誘発した.
- アクティビンは同じ条件下では筋肉形成を誘導しなかった.
- プラズミド注射によるノギン発現は,腹部化胚における部分的に救済された背面パターン.
結論:
- この発見は,ノギン遺伝子の産物が,スペーマンのオーガナイザーから発するドルザライジング信号であることを強く示唆しています.
- ノーギンは,胚の発達中の背中腹部のパターンを確立する上で重要な役割を果たします.
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