新しい脊椎動物の頭の進化は,古代の状骨格組織のコオプションによるものです
David Jandzik1, Aaron T Garnett2, Tyler A Square2
11] Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado 80309, USA [2] Department of Zoology, Comenius University, Bratislava 84215, Slovakia.
Nature
|December 10, 2014
まとめ
脊椎動物の頭部骨格は,新しい組織からではなく,既存の軟骨のような組織の広がりから進化したのかもしれない. 遺伝子調節の変化,特にSoxEは,ニューラルクレスト細胞におけるこの進化的移行を容易にした可能性が高い.
科学分野:
- 進化的発達生物学 進化的発達生物学
- 比較解剖学の比較解剖学について
- 塩基配列生物学について
背景:
- 脊椎動物の頭部骨格は,細胞軟骨によって特徴づけられ,しばしば神経の頂上細胞から派生します.
- 脊椎動物の頭部骨格の進化的起源は,神経から派生した軟骨の出現と関連しています.
- 神経頂部細胞とその由来する軟骨は,脊椎動物に特異的に存在すると考えられています.
研究 の 目的:
- 脊椎動物の頭部骨格の進化の起源を調査する.
- 脊椎動物における脊椎動物の軟骨と神経の細胞の潜在的前駆者を特定する.
- 軟骨発達の進化における遺伝子調節の役割を理解する.
主な方法:
- ブランキオストマ・フロリダ科 (Branchiostoma floridae) (フロリダ・アンフィオクサス) の幼虫の軟骨のような組織に対する分析.
- コード生物の進化におけるSoxE遺伝子とその調節要素の調査.
- 比較的なゲノムと発達分析.
主要な成果:
- 脊椎動物の細胞軟骨の特徴を持つ一時的な組織は,アンフィオクサス幼虫で特定されました.
- 証拠によると,SoxE遺伝子は進化の過程で新しいシス調節配列を獲得した.
- ニューラル・クライスト細胞におけるSoxEの新種の発現は,これらの新しい調節配列によって導かれていた.
結論:
- 脊椎動物の頭部骨格は,以前に存在していた軟骨のような組織の拡張によって進化した可能性が高く,新しい組織の発明によって進化しなかった.
- SoxEのような古代遺伝子のシス調節要素の進化的変化は,神経の頂上細胞における組織発達の方向づけに決定的であった.
- これは,脊椎動物の頭蓋骨構造の起源に関する新しい視点を提供します.
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