現代の鳥インフルエンザウイルスの内部遺伝子の同期した世界的な掃描
Michael Worobey1, Guan-Zhu Han1, Andrew Rambaut2
1Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, USA.
Nature
|February 18, 2014
まとめ
系統遺伝学的分析は,インフルエンザAウイルス (IAV) の宿主系統が独立して進化することを明らかにしています. この発見は,動物性感染症の発生を理解し,鳥類や人間などの宿主間のウイルスの流れを追跡するために不可欠です.
科学分野:
- ウイルス学 ウイルス学 ウイルス学
- 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:
- 動物性感染症,特にインフルエンザAウイルス (IAV) は,世界的な健康に重大なリスクをもたらす.
- IAVのようなRNAウイルスの出現を促す進化的メカニズムは,まだ完全に理解されていません.
- ウイルスの起源と宿主間の伝播ダイナミクスを追跡するために,正確な系統遺伝的推論は不可欠です.
研究 の 目的:
- 信頼性の高い系統遺伝的推論において,異なるIAV宿主系統の独立した分子進化率の必要性を調査する.
- IAVの進化史と宿主関連系を,新しい系統遺伝学的アプローチを用いて再評価する.
- パンデミックの原因となるものを含む,重要なIAV株の起源と進化経路を解明する.
主な方法:
- ホスト特異的なローカルクロックモデルを組み込み,系統間の独立した進化速度を可能にする系統分析.
- "リラックスした"分子時計モデルを含む伝統的な方法との結果の比較.
- IAVの全ゲノムセグメントの進化史の再構築.
主要な成果:
- "リラックスした"時計モデルとは対照的に,独立した進化速度を明示的にモデリングすることは,正確なIAVの系統遺伝学にとって重要である.
- 馬のH7N7系は,鳥類,人間,豚,馬のH3N8系と系統遺伝的に組み合わさっており,1800年代半ばから後半にかけて共通の祖先を共有しています.
- 両半球からの主要な鳥インフルエンザウイルス (AIV) 系統は1800年代後半に統合され,内部遺伝子の世界的な選択的な掃討を示しました.
結論:
- この研究は,IAVの進化と遺伝子フローを理解するための強力な枠組みを提供します.
- AIV内部遺伝子の世界的な選択的掃討は1800年代後半に始まり,後のウイルス系統に影響を与えました.
- この進化の歴史は,1918年のパンデミックウイルスと1963年の馬のH3N8パンゾオティックウイルスの出現に特定のAIV系統を伴う.
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