Regulation of Three-Dimensional Epithelial Cell Shape in a Two-Dimensional Tissue

Three-dimensional force distribution within the actin cytoskeleton of epithelial tissue regulates cell shape. While two-dimensional cell shape has been well characterized and heavily studied, three-dimensional cell shape regulation is less well understood despite its critical role in large scale epithelial processes such as invagination. By examining the relationship between cell height, density and biological components of the actin cytoskeleton, we explore the mechanisms by which the epithelial tissue regulates shape and volume. By probing the effect of external environmental forces on a tissue’s shape, we observe that while cell density is not a strong indicator of epithelial height, osmotic shock and substrate curvature drastically decreases both tissue height and cell volume while leaving the lateral shape of cells in the tissue undisturbed. In addition, we examine how the maturity of the tight junction regulates local volume and height correlation in the tissue.