Mox2は,手足の筋肉の発達を制御する遺伝的階層の構成要素です
B S Mankoo1, N S Collins, P Ashby
1Division of Developmental Neurobiology, MRC National Institute for Medical Research, London, UK.
Nature
|July 14, 1999
まとめ
Mox2遺伝子は,マウスの四肢筋肉の発達に不可欠であり,Pax3やMyf5.5のような重要な遺伝子を調節する. 欠乏すると,筋肉の質量が減り,筋肉が欠落し,脊椎動物の肢体ミオゲネシスにおけるその役割を強調する.
科学分野:
- 発達生物学 発達生物学とは
- 分子遺伝学 分子遺伝学
背景:
- 肢骨格筋は,パラキシアルメソダームの祖先から発達する.
- ミオジェニック調節因子 (MRF) とPax3は,哺乳類の筋肉発育に不可欠である.
- Mox1とMox2は,パラキシアルメソダームで発現する関連性のあるホメオボックス遺伝子です.
研究 の 目的:
- 脊椎動物の肢体ミオゲネシスにおけるMox2の役割を調査する.
- 尾筋の形成にMox2欠乏が及ぼす影響を判断する.
主な方法:
- Mox2.2のヌル変異に対する同胞性のマウスの分析.
- 変異性胚における四肢の筋肉の発達と遺伝子発現の評価
主要な成果:
- Mox2が欠けているマウスは,肢の筋肉質の減少と特定の筋肉の消失を示します.
- Mox2は,マイオジェニック前駆物質が肢芽に移動するには必要ありません.
- Mox2の欠乏は,肢芽にPax3とMyf5のダウンレギュレーションをもたらしますが,MyoDはそうではありません.
結論:
- MOX2ホメオプロテインは,正常な尾筋形成に不可欠である.
- Mox2は,手足の発達中にミオゲン遺伝子の発現を調節する上で重要な役割を果たします.
- Mox2は,脊椎動物の肢体ミオゲネシスの重要な調節剤である.
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