脊椎動物におけるチモポエーシスの出現を支える遺伝ネットワークの進化
Baubak Bajoghli1, Narges Aghaallaei, Isabell Hess
1Department of Developmental Immunology, Max-Planck Institute of Immunobiology, Stuebeweg 51, D-79108 Freiburg, Germany.
Cell
|June 30, 2009
まとめ
適応免疫は,古代の遺伝ネットワークの拡張を通じて,筋の発達とT細胞の特異性のための新しい遺伝子を組み込むことで,椎動物で進化した. このプロセスには,免疫システムの進化に不可欠な新しい信号伝達経路が含まれていました.
科学分野:
- 進化的免疫学について
- 比較ゲノミクスとは
- 発達生物学 発達生物学とは
背景:
- 適応性免疫防御は,約5億年前にのある脊椎動物で出現した.
- この出現は,胸腺のような革新と関連しており,その起源について疑問を投げかけました: de novo または古代のネットワークの詳細化.
研究 の 目的:
- 胸腺形成 (胸腺の発達) の根底にある遺伝的変化を再構築する.
- 重要な適応性免疫機能が古代の遺伝ネットワークから進化したのか,それとも新たな形で発生したのかを調査する.
主な方法:
- 比較的なゲノムと表情分析は,帯状動物と基礎脊椎動物間で行われました.
- 骨魚における派生遺伝子ネットワークモデルの実験的検証.
主要な成果:
- のない脊椎動物の上皮質の祖先のネットワークは,軟骨魚に拡張し,ケモカイン遺伝子を組み込みました.
- のある脊椎動物のリンパ球は,ケモカイン受容体発現のための新しいネットワークを進化させた.
- 補完的な変更により,T細胞系統の仕様のためのデルタ/ノッチシグナリングが容易になりました.
結論:
- のある脊椎動物の適応性免疫システムは,古代の遺伝ネットワークの発展によって進化したのであり,新たな創造物ではない.
- 比較的および実験的アプローチにより,チモポエーゼスとT細胞発達の進化的枠組みが明らかにされました.
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