Integrin alpha chains exhibit distinct temporal and spatial localization patterns in epithelial cells of the Drosophila ovary

Integrins are heterodimeric transmembrane receptors that modulate cell adhesion, migration, and signaling. Multiple integrin chains contribute to development and morphogenesis of a given tissue. Here, we analyze the expression of Drosophila integrin alpha chains in the ovarian follicular epithelium, a model for tissue morphogenesis and cell migration. We find expression throughout development of the beta chain, βPS. Alpha chains, however, exhibit both spatial and temporal expression differences. αPS1 and αPS2 integrins are detected during early and mid-oogenesis on apical, lateral, and basal membranes with the βPS chain, whereas αPS3-family integrins (αPS3, αPS4, αPS5) are expressed in anterior cells late in oogenesis. Surprisingly, we find that αPS3-family integrins are dispensable for dorsal appendage morphogenesis but play a role in the final length of the egg, suggesting redundant functions of integrins in a simple tissue. We also demonstrate roles for αPS3βPS integrin in border cell migration and in stretch cells.