Cell adhesion and cortex contractility determine cell patterning in the Drosophila retina

Abstract

Because of the resemblance of many epithelial tissues to densely packed soap bubbles, it has been suggested that surface minimization, which drives soap bubble packing, could be governing cell packing as well. We test this by modeling the shape of the cells in a Drosophila retina ommatidium. We use the observed configurations and shapes in wild-type flies, as well as in flies with different numbers of cells per ommatidia, and mutants with cells where Eor N-cadherin is either deleted or misexpressed. We find that surface minimization is insufficient to model the experimentally observed shapes and packing of the cells based on their cadherin expression. We then consider a model in which adhesion leads to a surface increase, balanced by cell cortex contraction. Using the experimentally observed distributions of E-and N-cadherin, we simulate the packing and cell shapes in the wild-type eye. Furthermore, by changing only the corresponding parameters, this model can describe the mutants with different numbers of cells or changes in cadherin expression.cell shape ͉ surface mechanics ͉ Cellular Potts model

Modeling Morphogenesisin silicoandin vitro: Towards Quantitative, Predictive, Cell-based Modeling

“…The Cellular Potts model (CPM), alternatively called Glazier-Graner-Hogeweg (GGH) model [16], is a popular cell-based method for simulating biological growth development (reviewed in [29]; more recent studies include [21,18,38,33,58]). The CPM was used to develop several of the in vitro vasculogenesis described in Section 2.2.1 ( Figure 3C, D and F), in combination with partialdifferential equations (PDE) to model the diffusion of secreted chemoattractants in the Matrigel.…”

Mechanical modulation of osteochondroprogenitor cell fate

“…gastrulation, mechanical forces (tensile) direct self assembly of the germ layers [Krieg et al 2008]. Similarly, cell adhesion and cell tension modulate the patterning of the retina in drosophila [Kafer et al 2007]. Hence, mechanical forces influence tissue phenotype throughout the pre-and perinatal time periods [Hall and Miyake 2000].…”

Physical modeling of cell geometric order in an epithelial tissue

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