Morphogenesis is regulated by genetic, biochemical, and biomechanical factors, but the feedback controlling the interactions between these factors remains poorly understood. A previous study has found that compressing the brain tube of the early chick embryo induces changes in contractility and nuclear shape in the neuroepithelial wall. Assuming this response involves mechanical feedback, we used experiments and computational modeling to investigate a hypothetical mechanism behind the observed behavior. First, we measured nuclear circularity in embryonic chick brains subjected to transverse compression. Immediately after loading, the circularity varied regionally and appeared to reflect the local state of stress in the wall. After three hours of culture with sustained compression, however, the nuclei became rounder. Exposure to a gap junction blocker inhibited this response, suggesting that it requires intercellular diffusion of a biochemical signal. We speculate that the signal regulates the contraction that occurs near the lumen, altering stress distributions and nuclear geometry throughout the wall. Simulating compression using a chemomechanical finite-element model based on this idea shows that our hypothesis is consistent with most of the experimental data. This work provides a foundation for future investigations of chemomechanical feedback in epithelia during embryonic development.

形态发生受遗传、生化和生物力学因素的调节，但控制这些因素之间相互作用的反馈仍然知之甚少。先前的一项研究发现，压缩早期鸡胚的脑管会导致神经上皮壁的收缩性和核形状发生变化。假设这种响应涉及机械反馈，我们使用实验和计算模型来研究观察到的行为背后的假设机制。首先，我们测量了受到横向压缩的胚胎鸡脑的核圆形度。加载后，圆度立即发生区域变化，似乎反映了壁中的局部应力状态。然而，经过三个小时的持续压缩培养后，细胞核变得更圆了。暴露于间隙连接阻滞剂抑制了这种反应，表明它需要生化信号的细胞间扩散。我们推测该信号调节了管腔附近发生的收缩，改变了整个壁的应力分布和核几何形状。基于这一思想使用化学机械有限元模型模拟压缩表明我们的假设与大多数实验数据一致。这项工作为胚胎发育过程中上皮细胞化学力学反馈的未来研究奠定了基础。基于这一思想使用化学机械有限元模型模拟压缩表明我们的假设与大多数实验数据一致。这项工作为胚胎发育过程中上皮细胞化学力学反馈的未来研究奠定了基础。基于这一思想使用化学机械有限元模型模拟压缩表明我们的假设与大多数实验数据一致。这项工作为胚胎发育过程中上皮细胞化学力学反馈的未来研究奠定了基础。