謎めいた色素の遺伝子複合体の進化における大規模変異
Romain Villoutreix1,2, Clarissa F de Carvalho1, Víctor Soria-Carrasco1
1Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
Science (New York, N.Y.)
|July 25, 2020
まとめ
構造的変異は,大きな欠損のように,有益な遺伝子複合体を包装することによって適応を促すことができます. この研究は,これらの"超変異"が 異なった昆虫の色変異を生じさせる方法を示し,以前の超遺伝子理論に 異議を唱える.
科学分野:
- 進化生物学
- 遺伝学
- 分子進化
背景:
- 野生の集団における適応の遺伝的基盤を理解することは極めて重要です
- 適応特性の形成における再結合抑制と新種の変異の役割は依然として議論されている.
- 構造的変異とその適応への影響はますます認識されています.
研究 の 目的:
- ティメマ・チュマッシュの 謎の色変異の 遺伝的構造を調べるため
- これらの形態の進化を駆動するメカニズム (再結合抑制 vs. 大規模な変異) を決定する.
- これらの適応的変化を維持する際のバランス選択と内進の相対的な貢献を評価する.
主な方法:
- 色差に関連した遺伝的位置の分析.
- 抑制された再結合と大規模変異の領域を特定するための比較ゲノミクス.
- 選択と遺伝子フローの役割を推測する集団遺伝分析.
主要な成果:
- 複数のリンクされたロシではなく 単一のスーパーゲンが ティメマ・チュマッシュの色変異の基礎です
- メガベーススケールのデレーション ("超変異") は,7つの *Timema* 種の緑色変異体で特定されました.
- バランスをとる選択は,これらの変異を維持する際の 侵入よりも強い力であるようです.
結論:
- 欠損などの大規模変異は遺伝子複合体を効果的に包み込み,適応を容易にする.
- 抑制された再結合 (スーパー遺伝子) と大きな変異は,モルフのような離散的適応単位の形成に寄与する.
- この研究は生物多様性を生み出し維持する 進化の様々な経路を強調しています
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