章魚のゲノムと頭足類の神経的および形態学的新しさの進化
Caroline B Albertin1, Oleg Simakov2, Therese Mitros3
1Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois 60637, USA.
Nature
|August 14, 2015
まとめ
章魚のゲノム配列解析は ゲノムの複製ではなく 遺伝子の拡張を明らかにし 複雑な神経系と 頭足類に特有の特徴を 引き起こすのです これは無脊椎動物における 新しい進化の経路を示しています
科学分野:
- ゲノミクス
- 進化生物学
- 神経科学
背景:
- コレオイド頭足類は 巨大な神経系を持ち カメラのような目や 洗練されたカモフラージュのような ユニークな適応を備えています
- これらの無脊椎動物の革新の 遺伝的基盤を調査することは 進化の分岐を理解するために 極めて重要です
研究 の 目的:
- 頭足類の脳と体の分子の基礎を調査し 章魚のゲノムを解析する
- 複雑な頭足類の特徴の進化に寄与する重要な遺伝的要因を特定する.
主な方法:
- カリフォルニアの二点章魚 (Octopus bimaculoides) のゲノムとトランスクリプトームの配列決定
- 遺伝子の拡張と再編成を特定するための比較ゲノム分析
- メッセンジャーRNA編集と頭足類特有の遺伝子の分析
主要な成果:
- 全ゲノム複製の証拠はない
- 以前は脊椎動物特有と考えられていた プロトカデリンとC2H2の亜鉛指遺伝子の大量拡大.
- 神経組織と皮膚に高い発現率を持つ数百の頭足類特異遺伝子の特定
- 移植可能な要素の拡張に関連した大規模なゲノム再編成の発見
- タンパク質の多様性に寄与する重要なメッセンジャーRNA編集.
結論:
- 複雑な神経系を含む頭足類の形態学的革新は,特定の遺伝子ファミリーの実質的な拡大とゲノム再構成によって引き起こされます.
- ゲノム家族拡大とゲノム再編成は,全ゲノム複製ではなく,頭足類における重要な進化的メカニズムである.
- メッセンジャーRNA編集は頭足類のタンパク質機能をさらに多様化します
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