Nielsen Bjarke Frost, Nissen Silas Boye, Sneppen Kim, Mathiesen Joachim, Trusina Ala
Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100 Copenhagen, Denmark.
Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100 Copenhagen, Denmark.
iScience. 2020 Feb 21;23(2):100830. doi: 10.1016/j.isci.2020.100830. Epub 2020 Jan 11.
How do flat sheets of cells form gut and neural tubes? Across systems, several mechanisms are at play: cells wedge, form actomyosin cables, or intercalate. As a result, the cell sheet bends, and the tube elongates. It is unclear to what extent each mechanism can drive tube formation on its own. To address this question, we computationally probe if one mechanism, either cell wedging or intercalation, may suffice for the entire sheet-to-tube transition. Using a physical model with epithelial cells represented by polarized point particles, we show that either cell intercalation or wedging alone can be sufficient and that each can both bend the sheet and extend the tube. When working in parallel, the two mechanisms increase the robustness of the tube formation. The successful simulations of the key features in Drosophila salivary gland budding, sea urchin gastrulation, and mammalian neurulation support the generality of our results.
扁平的细胞片层是如何形成肠道和神经管的？在多个系统中，有几种机制在起作用：细胞楔入、形成肌动球蛋白束或插入。结果，细胞片层弯曲，管子伸长。目前尚不清楚每种机制在多大程度上能够独立驱动管子的形成。为了解决这个问题，我们通过计算探究是否一种机制，即细胞楔入或插入，就足以实现整个从细胞片层到管子的转变。使用一个以极化点粒子代表上皮细胞的物理模型，我们表明单独的细胞插入或楔入都可能足够，并且每种机制都既能使片层弯曲又能使管子延伸。当这两种机制并行起作用时，它们会提高管子形成的稳健性。对果蝇唾液腺出芽、海胆原肠胚形成和哺乳动物神经胚形成等关键特征的成功模拟支持了我们结果的普遍性。
