成人マウスの丸を決定する遺伝子Sryの円状転写
1Laboratory of Eukaryotic Molecular Genetics, Medical Research Council, National Institute for Medical Research, London, England.
Cell
|June 4, 1993
まとめ
性別決定に不可欠なSry遺伝子は,マウスの丸で円形のRNAトランスクリプトを形成する. これらの豊富な,円形のSryRNAは,細胞質に存在し,遺伝子の結果である可能性があります.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 発達生物学 発達生物学について
背景:
- Sry遺伝子は,哺乳類の雄性性決定に不可欠である.
- Sryの発現は,成人の testiclesで,その主な作用部である生殖器のリッジよりも高い.
- 大人の丸におけるSryの正確な機能は不明のままである.
研究 の 目的:
- ネズミの丸で見つかったSryトランスクリプトの異常な構造を調査するために.
- これらのSry RNA分子の性質と局所を特徴づけるために.
- これらの異常なトランスクリプトの潜在的な起源を探求するために.
主な方法:
- コンプリメンタリーDNA (cDNA) 隔離と5'ラピッドアンプリフィケーション・オブ・cDNA エンド (RACE).
- RNAase保護アッセイと逆転写ポリメラーゼ連鎖反応 (RT-PCR).
- オリゴヌクレオチドのハイブリッド化とRNAase Hの消化.
主要な成果:
- 丸のSryのトランスクリプトは,5'の位置で3'の配列を持つ異常な構造を示しています.
- これらの異常なトランスクリプトは,成人のマウスの丸で最も豊富に存在するSry RNA分子です.
- RNAase Hの消化とハイブリデーションにより,これらのSry RNA分子が円形であることを確認しました.
- 似たような円形のSryトランスクリプトは,異なるマウス亜種 (Mus musculus musculus, Mus musculus domesticus, Mus spretus) で検出されました.
- 円形のRNAは細胞質にあり,ポリソームと有意に関連していない.
結論:
- ネズミの丸におけるSryトランスクリプトは,円形のRNA分子である.
- 円形のSry RNAの形成は,Sryロカスを取り巻くユニークなゲノム構造の影響を受けた通常のスプライシングプロセスから生じる可能性が高い.
- サイトプラズマに円形のSryRNAが存在することは,成人の丸内の転写後の調節または機能における潜在的,まだ未確定の役割を示唆しています.
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