共生細菌における進行中のゲノム侵食のダイナミクスと時間スケール
Nancy A Moran1, Heather J McLaughlin, Rotem Sorek
1Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA. nmoran@email.arizona.edu
Science (New York, N.Y.)
|January 20, 2009
まとめ
Buchnera aphidicolaのような共生細菌は,高変異率のため,急速なゲノム減少を示しています. この研究は,進行中の遺伝子喪失とDNAの消去を明らかにし,共生生物のゲノム進化のモデルを提供している.
科学分野:
- 微生物学 微生物学とは
- 進化生物学の進化生物学について
- ゲノミクスゲノミクスとは
背景:
- シンビオティックなバクテリアは,極度のゲノム縮小を経験します.
- 以前の研究は,共生生物のゲノム侵食の動態に関する限られた洞察を提供していた.
研究 の 目的:
- シンビオントゲノムの進化的動態を文書化するために.
- pea aphid の宿主から Buchnera aphidicola のゲノム減少を調査するために.
主な方法:
- Buchnera aphidicola の7つの株の配列を決定しました.
- 自発的な変異率の推定.
- 挿入/削除率と遺伝子喪失の分析.
主要な成果:
- Buchnera aphidicolaの高自発変異率 (≥4x10^-9) が推定され,他の細菌の比率を上回りました.
- DNAホモポリマーでは,より大きな削除とともに,頻繁に小さな挿入/削除が発生しました.
- 精製された選択にもかかわらず,共生生物のゲノムで進行中の遺伝子とDNAの損失が観察されました.
結論:
- Buchnera aphidicolaは,高変異率を示し,ゲノムの縮小を促しています.
- 変異,選択,遺伝子喪失を含むシンビオントのゲノム減少のための段階的なモデルが提案されています.
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