自然選択とジングウェイの起源,ドロソフィラのキメリック処理された機能性遺伝子
1Section of Genetics, University of California, Davis 95616.
Science (New York, N.Y.)
|April 2, 1993
まとめ
ドロソフィラの処理された遺伝子,以前は擬似遺伝子であったが,jingwei.と呼ばれる新しい機能性遺伝子へと進化した. この遺伝子の起源には,別の遺伝子からDNAを捕獲することが含まれ,新しい遺伝子の進化における自然選択の役割を実証しています.
科学分野:
- 進化生物学の進化生物学について
- 分子遺伝学 分子遺伝学
- ゲノミクスゲノミクスとは
背景:
- 新しい遺伝子の発生は,進化の根本的なプロセスである.
- 遺伝子の起源を理解するには,分子機構と集団動態の両方を検討する必要があります.
- 処理されたドロソフィラのアルコール脱水素酶 (Adh) 遺伝子は,当初は擬似遺伝子と考えられていたが,新しい遺伝子形成を研究するためのユニークなモデルを提供した.
研究 の 目的:
- 新しい機能的な遺伝子の起源に関与する分子イベントと集団動態を調査する.
- 無関係なDNA配列の捕獲によって形成されたキメリック遺伝子の進化軌道を分析する.
- 新種の遺伝子の出現およびその後の進化における自然選択の役割を決定する.
主な方法:
- 処理されたAdh遺伝子の配列分析と,その統合を新しい遺伝的位置にします.
- 新型キメリック遺伝子とその親であるAdh遺伝子との間の遺伝子発現パターンの比較.
- 新しい遺伝子の分子進化率の評価.
主要な成果:
- 処理されたAdhメッセンジャーRNA配列は,関係のない遺伝子の上流エクソンとイントロンを捕獲することによって,jingweiと名付けられた新しい機能性遺伝子に組み込まれました.
- 新型キメリック遺伝子であるjingweiは,その親であるAdh遺伝子と比較して明確な発現パターンを示した.
- 分子進化の速度は,jingwei遺伝子とオリジナルのAdh遺伝子の間で異なっていた.
- 証拠は,自然選択がジンウェイ遺伝子の起源と進化に役割を果たしたことを示唆しています.
結論:
- この研究は,エクソン捕獲とキメリック遺伝子の形成を通じて,新しい遺伝子の誕生のための妥当な経路を示しています.
- ジングウェイ遺伝子は,ゲノム形成における分子革新と自然選択の相互作用を理解するためのケーススタディとして役立つ.
- 新しい機能性遺伝子は,以前は機能しなかった遺伝要素から,再結合と規制の過程で発生することがあります.
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