鳥類の肢芽におけるHox-4.6の標的化された誤発現は,明らかにホメオティックな変異を引き起こします
B A Morgan1, J C Izpisúa-Belmonte, D Duboule
1Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115.
Nature
|July 16, 1992
まとめ
発達する四肢におけるホックス-4.6遺伝子発現は,四肢の発達に影響を与えます. 表現領域を変化させるとパターンが変化し,前後軸に沿って四肢のアイデンティティを特定する役割が示唆される.
科学分野:
- 発達生物学 発達生物学とは
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
背景:
- ホックス遺伝子のクラスター,特にホックス-4遺伝子は,四肢芽の内にある内蔵ドメインで発現します.
- これらの発現領域は,発達する肢体構造の前後軸と相関する.
- 以前の研究では,ホックス遺伝子が位置的アイデンティティを指定することを示唆しており,外科操作実験によって支持されています.
研究 の 目的:
- Hox-4.6遺伝子の発現が,四肢の前後軸に沿った位置的同一性を指定するという仮説を直接テストするために.
- Hox-4.6遺伝子発現ドメインを実験的に変えてインビボ効果を調査する.
主な方法:
- 複製に適したレトロウイルスベクトルを遺伝子操作に利用した.
- 手足の発達中のHox-4.6遺伝子の発現領域を前頭部に拡張した. in vivo.
- 発達する肢体のパターンの変化を観察し,分析した.
主要な成果:
- Hox-4.6遺伝子の発現領域の拡張は,以前は再現可能なパターンの変化をもたらしました.
- これらの変異は,後部ホメオティック変異と一致していた.
- Hox-4.6発現領域と四肢のパターンの間の直接的なリンクが示されました.
結論:
- Hox-4.6遺伝子は,発達する肢体の前後軸に沿った位置的アイデンティティを指定する上で重要な役割を果たします.
- Hox-4.6発現ドメインの実験的変異は,手足の形態発生に直接影響を及ぼします.
- この発見は,Hoxの転写因子の役割が,四肢の発達中の前後部パターンを確立することを支持しています.
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