神経頂部と中枢神経系の祖先の拡張に Wnt 信号が必要である
M Ikeya1, S M Lee, J E Johnson
1Centre for Molecular and Developmental Biology, Faculty of Science, Kyoto University, Japan.
Nature
|November 14, 1997
まとめ
二重のWnt信号伝達 (Wnt-1とWnt-3a) は,脊椎動物の中枢神経系の発達に不可欠である. これらの結合の欠如は,ニューラル・クライスト・デリバティブとドーサル・ニューラル・プリキュラサーの膨張を阻害し,中枢神経系のパターニングにおける非冗長な役割を明らかにする.
科学分野:
- 発達生物学 発達生物学とは
- 神経科学は神経科学である.
- 遺伝学 遺伝学とは
背景:
- 細胞の相互作用は,脊椎動物の中央神経系 (CNS) のパターニングを導く.
- Wnt-1とWnt-3aは,発達中の神経管の背中線で共発現する.
- 個々のWnt-1またはWnt-3a遺伝子の削除は,背部の神経管の欠陥を引き起こさないので,機能的な冗長性を示唆します.
研究 の 目的:
- 早期の中枢神経系の発達におけるWnt-1とWnt-3aの組み合わせられた役割を調査する.
- Wnt信号がニューラル・クライストと背部のニューラル前駆体形成に不可欠であるかどうかを判断する.
- Wnt信号がCNSのパターニングに影響を与えるメカニズムを解明する.
主な方法:
- Wnt-1およびWnt-3a遺伝子が両方欠けている二重変異マウス胚の分析.
- ニューラル・クライストの誘導体形成の評価.
- 神経管内のドロスラテラル神経前駆体集団の定量化.
主要な成果:
- Wnt-1とWnt-3aの両方の欠如は,ニューラル・クライストの誘導体の有意な減少につながります.
- ダブルミュータントは,ドロソラテラル神経前駆体の有意な減少を示しています.
- 観察されたフェノタイプは,背中中極性 (dorsoventral polarity) の確立における障害と関連していません.
結論:
- Wnt-1とWnt-3aのシグナル伝達は冗長ではなく,神経頂部と背部の神経前駆体の適切な発達に不可欠です.
- 局所的なWntシグナリングは,発達中の中枢神経系の背面神経前駆体の拡張を調節する.
- この発見は,哺乳類の神経管の発達におけるWnt信号伝達の役割の一般的なモデルを示唆しています.
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