明らかに冗長な転写増強剤によって授与されるフェノタイプの強度
Nicolás Frankel1, Gregory K Davis, Diego Vargas
1Howard Hughes Medical Institute and Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey 08544, USA.
Nature
|June 1, 2010
まとめ
ドロソフィラの発達における二次増強剤は,堅固な特徴形成を保証する. 欠落すると,環境的ストレスや遺伝的多様性による欠陥が生じ,現象型の安定性における重要な役割を強調する.
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:
- 遺伝子は遺伝子調節のために,転写増強剤を含むシス調節領域を利用する.
- 発達遺伝子はしばしば,同様の発現パターンを駆動する複数の強化モジュール (プライマリおよびセカンダリ) を有する.
- 副次増強剤は,環境および遺伝的変化に対する現象型の強さを授与すると仮定されています.
研究 の 目的:
- フェノタイプ性強度を与える二次増強剤の役割を調査する.
- 余剰増強剤の活性が特性の安定性を保証するという仮説を検証する.
主な方法:
- ドロソフィラのシェーブンベイビー (svb) 遺伝子の二次増強剤を欠いた欠陥変異体を生成した.
- 理想的な,低温,高温の胚発達条件下でトリコムのパターニングの欠陥を評価した.
- 翼のない遺伝子の投与量を減らすという文脈で,二次増強剤の除去がトリコームのパターニングに与える影響を分析した.
主要な成果:
- 二次増強剤の欠如は,最適な温度では軽微な欠陥を引き起こしたが,極端な温度では大きなトリコム損失を引き起こした.
- 温度に依存する欠陥は,二次増強剤によって駆動された,svb cDNAを発現するトランスゲンによって救出されました.
- 副次増強剤の喪失は,翼のない遺伝子の複製数が減少したハエのトリコムの欠陥を悪化させた.
結論:
- 二次増強剤は,特に環境ストレス下では,表型の強度を維持するために重要である.
- これらの増強剤は,遺伝的変異に対するバッファリングにおいて重要な役割を果たし,一貫した特性の発達を保証します.
- この発見は,複数の強化剤が発達安定に寄与するという仮説を裏付けている.
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