斑马鱼胚胎的左右对称性需要一定表面张力
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
概括
胚胎体内长度最初会出现错误,导致不对称. 然而,组织表面张力在形成后积极重塑 somites,确保斑马鱼的精确和对称的身体细分.
科学领域:
- 发育生物学
- 生物物理
- 胚胎发生
背景情况:
- 脊椎动物的胚胎发育包括定期细分为双边体.
- 传统上认为在形态发生之前,somite的前后长度,位置和对称性是分子决定的.
研究的目的:
- 在斑马鱼胚胎中研究初始索米特前后长度和位置的精度.
- 确定纠正初始不对称性并确保某种形态对称性的机制.
主要方法:
- 在体内观察斑马鱼胚胎发育的实验.
- 在实验室中单体体扩展培养.
- 机械建模分析组织表面张力效应.
- 表面张力分子 (整体蛋白,纤维蛋白) 和细分时钟组件的破坏.
主要成果:
- 最初的前后长度和位置不准确,导致左右不对称.
- 在形成后一小时内调整前后长度,增强形态对称性.
- 长度的调整是通过形状的变化 (前后侧被中侧补偿) 而不会改变体积.
- 通过整体蛋白和纤维蛋白介导的表面张力驱动了长度调整.
- 细分时钟不参与这种形成后的长度调整过程.
结论:
- 组织表面张力是纠正初始体长不准确并确保胚胎对称性的关键机制.
- 这种由表面张力驱动的过程代表了与细分时钟不同的机制,用于实现精确的形态细分长度.
- 这些发现表明组织表面张力作为胚胎组织发育中的形状调整和精度的一般原则.
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