Physics of Life Processes, Leiden Institute of Physics, Universiteit Leiden, 2333 CC, Leiden, The Netherlands.
Centre for Cell Biology of Chronic Disease, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia.
Nat Commun. 2023 Sep 16;14(1):5762. doi: 10.1038/s41467-023-41449-6.
Changes in tissue geometry during developmental processes are associated with collective migration of cells. Recent experimental and numerical results suggest that these changes could leverage on the coexistence of nematic and hexatic orientational order at different length scales. How this multiscale organization is affected by the material properties of the cells and their substrate is presently unknown. In this study, we address these questions in monolayers of Madin-Darby canine kidney cells having various cell densities and molecular repertoires. At small length scales, confluent monolayers are characterized by a prominent hexatic order, independent of the presence of E-cadherin, monolayer density, and underlying substrate stiffness. However, all three properties affect the meso-scale tissue organization. The length scale at which hexatic order transits to nematic order, the "hexanematic" crossover scale, strongly depends on cell-cell adhesions and correlates with monolayer density. Our study demonstrates how epithelial organization is affected by mechanical properties, and provides a robust description of tissue organization during developmental processes.
在发育过程中，组织几何形状的变化与细胞的集体迁移有关。最近的实验和数值结果表明，这些变化可以利用不同长度尺度上的向列相和六方相取向有序的共存。目前尚不清楚这种多尺度组织如何受到细胞及其基质的材料特性的影响。在这项研究中，我们研究了具有不同细胞密度和分子谱的 Madin-Darby 犬肾细胞单层中的这些问题。在小尺度上，无论是否存在 E-钙黏蛋白、单层密度和底层基质硬度，融合单层都以突出的六方有序为特征。然而，这三个特性都影响了中尺度组织的组织。六方有序向向列有序转变的尺度，即“六向性”交叉尺度，强烈依赖于细胞-细胞黏附，并与单层密度相关。我们的研究表明上皮组织的组织如何受到机械性能的影响，并为发育过程中的组织组织提供了稳健的描述。
