ホメオボックスを含む遺伝子で,Xenopusのオオゲネシス中に発現する

M M Müller, A E Carrasco, E M DeRobertis

Cell

|November 1, 1984

まとめ

研究者らは,ドロソフィラの遺伝子に似たホメオドメインを持つ新しいXenopus遺伝子を分離しました. この遺伝子は卵細胞で高度に転写され,初期の胚細胞の細胞タイプ決定における役割を示唆しています.

科学分野:

発達生物学発達生物学とは
分子生物学は分子生物学である.
遺伝学遺伝学とは

背景:

ホメオボックス遺伝子は,様々な種の胚の発達に不可欠です.
以前のXenopus homeobox遺伝子の隔離は,保存された発達経路を強調しました.
ドロソフィラのホメオティック遺伝子は,アンテナペディアのように,遺伝子機能を理解するための重要なモデルとして機能します.

研究の目的:

クセノプスの第2のホメオボックスを含む遺伝子の分離と特徴を報告する.
ホメオドメインの配列の進化的保存を調査する.
初期のXenopus胚形成におけるこの遺伝子の潜在的な役割を調査する.

主な方法:

Xenopus laevisからの遺伝子分離と配列決定.
既知の遺伝子を持つホメオドメインのホモロジー分析 (Drosophila Antennapedia,以前に隔離されたカエルの遺伝子).
Xenopusの卵細胞における遺伝子転写レベルの分析.

主要な成果:

ホメオドメインを持つ新しいXenopus遺伝子の分離.
ドロソフィラ・アンテナペディアによるホメオドメインの高シーケンス保存 (59/60アミノ酸)
重要な保存 (54/60アミノ酸) は,以前に確認されたカエルのホメオボックス遺伝子.
大型のXenopus卵細胞における遺伝子の豊富な転写.
ポリグルタミン酸の尾を持つユニークなカルボキシ末端の識別.

結論:

新しく分離されたXenopus遺伝子は,開発に潜在的に関与する保存されたホメオボックスを含む遺伝子を表しています.
卵細胞での豊富な転写は,母親の遺伝子発現における役割を示唆しています.
タンパク質製品は,Xenopus.の胚細胞タイプを早期に決定する上で重要な役割を果たす可能性があります.

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