アロテトラプロイドのカエルのゲノム進化 Xenopus laevis
Adam M Session1,2, Yoshinobu Uno3, Taejoon Kwon4,5
1University of California, Berkeley, Department of Molecular and Cell Biology and Center for Integrative Genomics, Life Sciences Addition #3200, Berkeley, California 94720-3200, USA.
Nature
|October 21, 2016
まとめ
Xenopus laevisのゲノムは 3400万年前に分離した2つの祖先種から アロテトラプロイドの起源を示しています このゲノム複製は 遺伝子の保持と非対称なサブゲノム進化に影響します
科学分野:
- 比較ゲノミクス
- 進化生物学
- 両生類の遺伝学
背景:
- テトラプロイジは全ゲノム複製のイベントで 進化的イノベーションの重要な原動力です
- アフリカの爪 (Xenopus laevis) は,複雑な進化の歴史を持つアロテトラプロイド種である.
- テトラプロイド種のゲノム構造と進化軌道を理解することは,ゲノム進化の解読に極めて重要です.
研究 の 目的:
- Xenopus laevisのテトラプロイドの起源と進化的結果を調査する.
- アロテトラプロイドのXenopus laevisのゲノムとその二倍体の親戚のXenopus tropicalisを比較する.
- X. laevisのサブゲノム組成と進化動態を特徴づける.
主な方法:
- Xenopus laevisとXenopus tropicalisのゲノムシーケンスについて
- X. laevisのゲノムをホモエオロギー的なサブゲノムに分割するためのバイオ情報分析.
- 転置可能な元素と擬似遺伝子の識別と分析により,分岐とポリプロイド化の時間を推定する.
- 遺伝子保持,タンパク質機能,遺伝子発現,配列保存の比較分析
主要な成果:
- Xenopus laevisのゲノムは2つの異なったホモエオロジックサブゲノムに分割され,独特の移植可能な要素ファミリーによって特徴付けられました.
- ~3400万年前 (マ) の祖先種と, ~17~18万年前 (マ) のアロテトラプロイデーションの見積もり.
- 遺伝子の56%以上が同質複製で保持され,保持率はタンパク質機能,遺伝子発現,横断配列保存と相関していた.
- サブゲノムの非対称的な進化で,一つは祖先の状態を保ち,もう一つは重要な遺伝子喪失,再編成,および表現の減少を経験しています.
結論:
- この研究は,Xenopus laevisのアロテトラプロイド起源を明らかにし,その形成のタイミングとメカニズムの洞察を提供します.
- X. laevisのゲノム複製は,遺伝子の保持と非対称なサブゲノムの進化をもたらし,現在の遺伝的景観を形作りました.
- これらの発見は,ポリプロイドの脊椎動物におけるゲノム進化と,全ゲノム複製イベントの機能的結果のより広範な理解に寄与する.
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