D.メラノガスターにおけるハイブリッド変異は,DNA転置のための一般的な放出メカニズムではありません
Science (New York, N.Y.)
|September 4, 1987
まとめ
P要素DNAの動きによって引き起こされるDrosophila melanogasterのハイブリッド変異は,一般的に他の転置可能な要素の活性を増やさない. これは,転置可能な要素の動きに対する調整された制御が制限されていることを示唆しています.
科学分野:
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
- 進化生物学の進化生物学について
背景:
- 自発的な変異は,DNA要素の挿入/外出によってしばしば発生する.
- 進化的圧力は,転置可能な要素 (TE) の移動性を制御するメカニズムを好む可能性が高い.
- P元素の移動に関連したドロソフィラ・メラノガスターのハイブリッド変異は,遺伝的不安定性を引き起こします.
研究 の 目的:
- ハイブリッド・ディスジェネシスが TE 運動を広く刺激するかどうかを調査する.
- P元素の活性がドロソフィラの他のTEsに影響するかどうかを判断する.
主な方法:
- 12のDNA要素にP要素誘発のハイブリッド変異効果を評価した.
- 16の変異性アレルの解離率の変化を調べた.
- 挿入性突然変異における変異変異状態の誘導をテストした.
主要な成果:
- ハイブリッド・ディスジェネシスは,テストされたDNA要素の切除率を有意に増加させなかった.
- P元素の活動は,他の転置可能な元素の突然変異を大きく誘導しなかった.
結論:
- P元素媒介のハイブリッド変異は,ドロソフィラの他のTEファミリーの一般的な活性化剤ではありません.
- TE運動に対する協調的な遺伝的コントロールは,普遍的ではなく,特異的と思われる.
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