Authors: S. Hilgenfeldt, S. Erisken, I. Gemp, and R. W. Carthew

The complex, highly reproducible shapes of ommatidia in the Drosophila eye are crucially dependent on cadherin expression in the adherens junctions of cells. We show that not only the overall tissue organization, but the shape of each individual cell can be understood through quantitative modeling using minimization of an interfacial energy functional. The model contains only two free parameters, encoding for the adhesion strengths of E- and N-cadherin, and reproduces interfacial angles and lengths in the adherens junction to within a few percent accuracy. Characteristic morphological changes in mutant ommatidia can be modeled within this approach, indicating that changing levels of cadherin expression may be important for shape evolution during morphogenesis.