ドロソフィラのダブルセックス遺伝子は,関連する性特異ポリペプチドをコードする,代替的にスプライスされたmRNAを生成することによって,体性差異化を制御する
1Department of Biological Sciences, Stanford University, California 94305.
Cell
|March 24, 1989
まとめ
フルーツハエのダブルセックス (dsx) 遺伝子は,代替スプライシングを使用して,男性と女性の特異的なメッセンジャーRNAsを作成します. このプロセスは,両性における性差異の調節に極めて重要です.
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:
- ダブルセックス (dsx) 遺伝子は,ドロソフィラ・メラノガスターの体性差異化の主な調節因子である.
- dsx遺伝子の2つの異なる機能的産物は,性別に応じて男性または女性の差別化を抑制する責任を負う.
研究 の 目的:
- 双性 (dsx) 遺伝子の性特異的調節の基礎にある分子機構を解明する.
- 代替スプライシングとポリアデニレーションが,男性と女性特有のdsx mRNAsの生成にどのように貢献するか調査する.
主な方法:
- 代替スプライシングとポリアデニレーションを含むプライマリトランスクリプト処理の分析.
- dsx発現に関与する規制要素の遺伝子および分子特性.
- 男性と女性の特定のmRNA構造とエンコードされたポリペプチドの比較.
主要な成果:
- dsx遺伝子は,共通のプライマリトランスクリプトを生成し,交互に性特異のmRNAに分割されます.
- これらのmRNAは共通の5'エクソンを共有するが,代替の3'エクソンを利用し,その結果,コードされたタンパク質の性別特異なカルボキシル末端を生成する.
- 遺伝データは,トランスフォーマーとトランスフォーマー-2のロケーション経由でDSX発現を調節する女性特有のスプライス受容体部位近くの配列を意味しています.
結論:
- dsxプライマリトランスクリプトの代替スプライシングは,機能的な性特異タンパク質を生成するメカニズムです.
- 性別特異的な3'エクソンは,男性と女性の性差別化におけるdsxの明確な役割を決定する.
- トランスフォーマーおよびトランスフォーマー-2遺伝子は,dsx mRNAの性別特異のスプライシングにおいて,規制的な役割を果たします.
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