ホメオボックスHox-4遺伝子の発現と,鶏の翼発達における位置の仕様

J C Izpisúa-Belmonte¹, C Tickle, P Dollé

¹European Molecular Biology Laboratory, Heidelberg, Germany.

Nature

|April 18, 1991

まとめ

チキンホックス-4ホメオゲネスは,翼の発達を調整する. レチノ酸は,ホックス-4遺伝子発現を誘発し,鏡像の数字パターンにつながり,これらの遺伝子が位置情報を提供す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について
分子遺伝学分子遺伝学

背景:

チキンホックス-4ホメオゲンは,マウスの同種に似ているように,胚の翼発達中に座標表現を示す.
ホックス遺伝子は,脊椎動物胚における前後パターンの確立に不可欠である.

研究の目的:

鶏の翼の発達中にホックス-4遺伝子発現を調節するレチノ酸の役割を調査する.
誘発されたHox-4遺伝子発現パターンが肢体形態の変化と相関するかどうかを判断する.

主な方法:

培養中の鶏の胚にレチノ酸を局所的に投与する.
in situ ハイブリダイゼーションまたは同様の技術を使用して,Hox-4遺伝子発現パターンの分析.
その後の数字の発展の観察と文書化.

主要な成果:

レチノ酸の投与は,Hox-4遺伝子のドーゼ依存の de novo 転写を誘導した.
誘発されたホックス-4遺伝子発現パターンは,鏡像の配列を形成した.
これらの鏡像表現パターンは,鏡像数字の形成の発展と相関していた.

結論:

レチノ酸はモルフォゲンとして作用し,四肢の発達中にHox-4遺伝子発現に影響を与えます.
Hox-4遺伝子は,四肢のパターンと数字のアイデンティティを確立するために必要な重要な位置情報をコードする可能性があります.
この発見は,階層化された形態遺伝子のシグナリングが,ホックス遺伝子調節を通して位置的同一性を指定するモデルを支持する.

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