クテノフォアのゲノムと神経系の進化的起源
Leonid L Moroz1, Kevin M Kocot2, Mathew R Citarella3
11] The Whitney Laboratory for Marine Bioscience, University of Florida, 9505 Ocean Shore Blvd, St Augustine, Florida 32080, USA [2] Department of Neuroscience & McKnight Brain Institute, University of Florida, Gainesville, Florida 32611, USA [3] Friday Harbor Laboratories, University of Washington, Friday Harbor, Washington 98250, USA.
Nature
|May 23, 2014
まとめ
クテノフォア (Ctenophora) とは,独特な神経系を有しており,最も初期の動物の系統を代表している可能性がある. 彼らのゲノムは独特の遺伝子内容を明らかにし,神経系の独立した進化を示唆しています.
科学分野:
- ゲノミクスゲノミクスとは
- 進化生物学の進化生物学について
- 動物学 動物学
背景:
- 複雑な動物の神経系の進化的起源は,ほとんど不明である.
- クテノフォア (コムゼリー) は,神経系とメソデームから派生した筋肉を有し,他の基礎メタゾアとは異なり,神経系とメソデームから派生した筋肉を有する.
- 彼らのユニークな生物学には,洗練された運動,行動,および発達が含まれています.
研究 の 目的:
- メタゾア内のクテノフォラの進化的配置を調査する.
- クテノフォアのゲノムとトランスクリプトミックの内容を分析する.
- クラノフォアにおける神経系と筋肉系の独立した進化を理解する.
主な方法:
- プレオロブラキア・バケイ (太平洋海) のゲノム配列決定の草案.
- さらに10種のクテノフォアのトランスクリプトーム配列解析.
- 神経性,免疫性,発達性遺伝子を含む遺伝子ファミリーの比較ゲノム分析.
- メタボロミックおよび生理学的データ分析.
主要な成果:
- クテノフォアのゲノムは,他の動物と比較して,神経原性,免疫性,および発達性遺伝子の含有量において顕著な違いを示しています.
- 統合的な分析により,Ctenophoraはメタゾア群の中で最も初期の分岐する系統である可能性があることが示唆されています.
- HOX遺伝子の欠如,正規のマイクロRNA機構,および免疫補完体の減少は,この仮説を支持する.
- 多くの双極性ニューロン特異性遺伝子と古典的な神経伝達物質経路遺伝子は,クテノフォアで存在しないか,または神経で発現しない.
結論:
- Ctenophoraは,メタゾア内の基礎系を表し,他の動物の最後の共通の祖先より前に潜在的に分岐している.
- クテノフォアの神経系と,おそらく筋肉の特異性は,他の動物の神経系と独立して進化した.
- クテノフォアのユニークなゲノムと遺伝子組成は,初期の動物の進化と複雑な特徴の独立した起源についての洞察を提供します.
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