ゼブラフィッシュ の 胚 の 左 右 の 対称性 は,表面 の 張力 を 要求 する
Sundar R Naganathan1, Marko Popović2,3,4, Andrew C Oates5
1Institute of Bioengineering, École polytechnique fédérale de Lausanne, Lausanne, Switzerland. sundar.naganathan@epfl.ch.
Nature
|April 28, 2022
まとめ
胚性ソミットの長さは最初は誤りで形成され,不対称性が生じます. しかし,組織の表面張りは,形成後のソミットを活性的に再構成し,斑馬魚の正確な対称的な体分割を保証します.
科学分野:
- 発達生物学
- バイオ物理学
- 胚形成
背景:
- 脊椎動物の胚の発達には,二極ソミットに周期的な分割が含まれます.
- ソミットの前後の長さ,位置,対称性は,形態発生前に分子的に決定されていると伝統的に信じられています.
研究 の 目的:
- ゼブラフィッシュの胚の初期ソミット前後部の長さと位置の精度を調査する.
- 初期非対称性を修正し,ある形態的対称性を確保するメカニズムを特定する.
主な方法:
- 斑馬魚の胚の発達を観察する in vivo 実験
- インビトロ単体体培養
- 組織表面張力効果を分析するための機械的モデリング
- 表面張力分子 (インテグリン,フィブロネクチン) とセグメンテーションクロック部品の破壊
主要な成果:
- 初期ソミット前後部の長さと位置は不正確で,左から右の非対称性を引き起こします.
- 形成後1時間以内に前後部の長さを調整し 形態的対称性を高めます
- 長さの調整は,体積の変化なしに形状の変化 (前後側側で補償される) により起こります.
- インテグリンとフィブロネクチンが介在するソミットの表面張りは,長さの調整を促します.
- セグメンテーションクロックは,この形成後の長さの調整プロセスには関与しません.
結論:
- 組織表面張りは,初期ソミット長さの誤差を修正し,胚の対称性を確保するための重要なメカニズムです.
- この表面張力駆動プロセスは,正確な形態学的セグメント長さを達成するためのセグメントクロックとは異なるメカニズムを表しています.
- この発見は,胚組織の開発における形状調整と精度の一般的な原則として,組織表面張力を示唆しています.
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