Tah Indrajit, Haertter Daniel, Crawford Janice M, Kiehart Daniel P, Schmidt Christoph F, Liu Andrea J
Speciality Glass Division, CSIR-Central Glass and Ceramic Research Institute, Kolkata, India.
Department of Physics and Astronomy, University of Pennsylvania, PA, USA.
ArXiv. 2023 Dec 20:arXiv:2312.12926v1.
Dorsal closure is a process that occurs during embryogenesis of . During dorsal closure, the amnioserosa (AS), a one-cell thick epithelial tissue that fills the dorsal opening, shrinks as the lateral epidermis sheets converge and eventually merge. During this process, the aspect ratio of amnioserosa cells increases markedly. The standard 2-dimensional vertex model, which successfully describes tissue sheet mechanics in multiple contexts, would in this case predict that the tissue should fluidize via cell neighbor changes. Surprisingly, however, the amnioserosa remains an elastic solid with no such events. We here present a minimal extension to the vertex model that explains how the amnioserosa can achieve this unexpected behavior. We show that continuous shrink-age of the preferred cell perimeter and cell perimeter polydispersity lead to the retention of the solid state of the amnioserosa. Our model accurately captures measured cell shape and orientation changes and predicts non-monotonic junction tension that we confirm with laser ablation experiments.
背侧闭合是在……胚胎发育过程中发生的一个过程。在背侧闭合期间，羊膜上皮（AS），一种填充背侧开口的单细胞厚上皮组织，随着外侧表皮层汇聚并最终融合而收缩。在此过程中，羊膜上皮细胞的长宽比显著增加。标准的二维顶点模型在多种情况下成功描述了组织片力学，在这种情况下它会预测组织应通过细胞邻域变化而流化。然而，令人惊讶的是，羊膜上皮仍然是一种弹性固体，并未发生此类事件。我们在此提出对顶点模型的一个最小扩展，以解释羊膜上皮如何实现这种意外行为。我们表明，首选细胞周长的持续收缩和细胞周长多分散性导致羊膜上皮保持固态。我们的模型准确地捕捉到了测量的细胞形状和取向变化，并预测了非单调的连接张力，我们通过激光消融实验证实了这一点。
