ユカリオットの強化要素における選択の安定化に関する証拠
M Z Ludwig1, C Bergman, N H Patel
1Department of Ecology and Evolution, University of Chicago, Illinois 60637, USA. mludwig@midway.uchicago.edu
Nature
|February 17, 2000
まとめ
増強剤のような遺伝子調節要素の進化的変化は,機能的な結果をもたらす可能性があります. この研究では,ドロソフィラ増強剤の配列の差異は,共同進化した変化によってマスクされ,遺伝子発現パターンに影響を与えることが示されています.
科学分野:
- 発達生物学 発達生物学とは
- 進化遺伝学の進化遺伝学について
- 分子生物学は分子生物学である.
背景:
- ユカリオットの遺伝子発現は,転写因子によって結合されたシス調節モジュール (強化剤) に依存しています.
- ドロソフィラ・メラノガスターの均等にスキップされたストライプ2要素は,特定の遺伝子発現パターンを制御するよく研究された強化剤です.
- 表現が保存されているにもかかわらず,増強配列は進化し,進化のパラドックスを示します.
研究 の 目的:
- シーケンスディバージェンスの機能的影響を,均等にスキップされたストライプ2エンハンスナーで調査する.
- 増強剤の進化的変化が遺伝子調節にどのように影響するかを理解する.
- ユカリオットの規制配列の進化のモデルを提案する.
主な方法:
- 異なる種からのネイティブストライプ2要素の半分を交換することによって,キメリック強化剤の構築.
- ドロソフィラ胚におけるこれらのキメリック強化剤によって誘発されるレポーター遺伝子発現の評価.
- 種間の増強剤元素の比較シーケンス分析.
主要な成果:
- 異なる種の半分を組み合わせて形成されたキメリック増強剤は,野生型のパターンのレポーター遺伝子発現を誘導することができなかった.
- 種間の増強剤の配列の違いは,遺伝子発現に機能的な影響を及ぼします.
- これらの機能的影響は,他の共同進化した配列修正によってマスクされているように見える.
結論:
- 増強剤配列の進化的変化は,遺伝子調節に機能的な影響を及ぼします.
- 同進化的プロセスは,個々の配列変異の機能的効果を覆い隠すことができます.
- これらの発見に基づいて,真核生物の調節配列の進化のモデルが提案されています.
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