Fig. 10. Integrin adhesion is not required for cell proliferation or establishment of epithelial polarity. (A) ßPS^- clones were induced by mitotic recombination in the wing disks of ß²/ß¹ larvae. Non-GFP expressing cells lack ßPS and ß. Bright green cells are the progeny of the wild type sibling cell from the mitotic recombination. Double integrin mutant clones proliferate as well as their twin spots, as seen by their similar size and cell number. (B,C) ßPS^- clones were induced in the follicular epithelium of ß²/ß¹ female egg chambers. The apicolateral surfaces of follicle cells are labelled with antibodies against DE-cadherin, and mutant cells lack GFP. Large clones lacking GFP are generated, indicating that follicle cell clones lacking both ß integrin subunits are able to proliferate. (B,B') Surface view of an egg chamber. DE-cadherin is localized to the cell cortex in double ß integrin mutant follicle cells. (C,C') Longitudinal confocal section through an egg chamber. Eliminating integrins from follicle cells causes multi-layering and cell shape defects. However, in mutant cells that have not yet completely rounded up, DE-cadherin is properly localized to the apicolateral surfaces.