Embryonic induction is a key mechanism in development that corresponds to an interaction between a signalling and a responding tissue, causing a change in the direction of differentiation by the responding tissue. Considerable progress has been achieved in identifying inductive signals, yet how tissues control their responsiveness to these signals, known as competence, remains poorly understood. While the role of molecular signals in competence has been studied, how tissue mechanics influence competence remains unexplored. Here we investigate the role of hydrostatic pressure in controlling competence in neural crest cells, an embryonic cell population. We show that neural crest competence decreases concomitantly with an increase in the hydrostatic pressure of the blastocoel, an embryonic cavity in contact with the prospective neural crest. By manipulating hydrostatic pressure in vivo, we show that this increase leads to the inhibition of Yap signalling and impairs Wnt activation in the responding tissue, which would be required for neural crest induction. We further show that hydrostatic pressure controls neural crest induction in amphibian and mouse embryos and in human cells, suggesting a conserved mechanism across vertebrates. Our work sets out how tissue mechanics can interplay with signalling pathways to regulate embryonic competence.

胚胎诱导是发育中的一个关键机制，对应于信号传导和响应组织之间的相互作用，导致响应组织分化方向的改变。在识别感应信号方面已经取得了相当大的进展，但组织如何控制它们对这些信号的反应（称为能力）仍然知之甚少。虽然分子信号在能力中的作用已经被研究，但组织力学如何影响能力仍有待探索。在这里，我们研究静水压在控制神经嵴细胞（一种胚胎细胞群）能力中的作用。我们发现，神经嵴能力随着囊胚腔（与预期神经嵴接触的胚胎腔）静水压的增加而降低。通过操纵体内静水压，我们发现这种增加会导致 Yap 信号传导受到抑制，并损害响应组织中的 Wnt 激活，而 Wnt 激活是神经嵴诱导所必需的。我们进一步表明，静水压力控制两栖动物和小鼠胚胎以及人类细胞中的神经嵴诱导，这表明脊椎动物之间存在保守机制。我们的工作阐明了组织力学如何与信号通路相互作用来调节胚胎能力。