MNR2ホメオドメインタンパク質によるモーターニューロンアイデンティティの特定
Y Tanabe1, C William, T M Jessell
1Howard Hughes Medical Institute, Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA.
Cell
|October 20, 1998
まとめ
ソニック・ヘッジホッグ (Shh) 信号はモーターニューロンの分化を誘導する. 新しい遺伝子であるMNR2は,重要な転写因子として機能し,モーターニューロンの発達を駆動し,その特性を確立するのに十分である.
科学分野:
- 発達神経科学とは
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- ソニック・ヘッジホッグ (Shh) 信号は,腹部神経管内のモーターニューロン分化に不可欠です.
- Shh信号をモーターニューロン分化と結びつける正確な分子機構は,まだ完全に理解されていません.
研究 の 目的:
- Shh媒介による運動ニューロン分化に関与する新しい遺伝子を特定する.
- 特定された遺伝子が,運動ニューロン発達の方向づけにおける役割を調査する.
主な方法:
- 単一のSHH誘発モーターニューロンからcDNAライブラリを差分スクリーニングする.
- 新型ホメオボックス遺伝子,MNR2.2の発現パターンの分析.
- 神経細胞におけるMNR2の胎外発現実験.
主要な成果:
- 新しいホメオボックス遺伝子であるMNR2が特定され,モーターニューロンの原始体で発現し,ポスミトーシスモーターニューロンで一時的に発現した.
- MNR2の胎外発現は,体内の運動ニューロン分化プログラムを誘発した.
- このプログラムには,特定のホームドメインのタンパク質,神経伝達物質のフェノタイプ,および軸索軌道の発現が含まれていました.
結論:
- 転写因子MNR2のShh媒介誘導は,体性運動ニューロン分化を直接するために十分である.
- MNR2は,モーターニューロンの重要な特徴を確立する上で重要な役割を果たします.
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