ヘンセン節の細胞の動きは,チキの左/右非対称遺伝子発現を確立する
Jerome Gros1, Kerstin Feistel, Christoph Viebahn
1Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
まとめ
チークの胚は,ノード近くの細胞の再編成を通じて,左/右の身体アシンメトリを確立します. この動きは遺伝子発現に影響を与え,非対称ドメインを作り,対称性を破ります.
科学分野:
- 発達生物学 発達生物学とは
- 胚学 胚学について
- 分子生物学は分子生物学である.
背景:
- 脊椎動物の左/右 (L/R) アナトミックな非対称性は,胃化の過程における分子イベントから生じます.
- チキン胚におけるL/R非対称性の確立の正確なメカニズムは不明である.
- L/R軸の定義における初期のステップは,種間で普遍的に保存されるわけではありません.
研究 の 目的:
- ニワトリの胚における左/右軸を定義する最古の出来事を調査する.
- 雛のL/R対称性破裂の基礎となる分子メカニズムを解明する.
- 非対称的な遺伝子発現パターンがどのように確立されるかを理解する.
主な方法:
- ガストルーレーション中のチキン胚内の細胞移動の分析.
- ソニック・ヘッジホッグ (Shh) とフィブロブラスト成長因子8 (Fgf8) を含む特定の遺伝子を発現する細胞集団の追跡.
- 細胞の移転と遺伝子発現パターンの関係を調査する.
主要な成果:
- 鶏の胚内で非対称な細胞の再編成が起こり,結節の周りの細胞が左へ移動する.
- ソニック・ヘッジホッグ (Shh) とフィブロブラスト・成長因子8 (Fgf8) を発現する細胞の相対的な移位は極めて重要です.
- これらの細胞の動きは,ShhとFgf8.8の非対称的な発現領域を被動的に確立します.
結論:
- 細胞の再編成は,純粋に固有の分子プログラミングではなく,雛のL/R非対称性を開始する上で重要な役割を果たします.
- 細胞移動による非対称的な遺伝子発現ドメインの被動的確立は,L/R対称性を破るための代替戦略を提供します.
- この発見は,脊椎動物のL / R軸の決定の保存されたおよび異なるメカニズムに関する新しい洞察を提供します.
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