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, beta PS. Alpha chains, however, exhibit both spatial and temporal expression differences. alpha PS1 and alpha PS2 integrins are detected during early and mid-oogenesis on apical, lateral, and basal membranes with the beta PS chain, whereas alpha PS3-family integrins (alpha PS3, alpha PS4, alpha PS5) are expressed in anterior cells late in oogenesis. Surprisingly, we find that alpha PS3-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 alpha PS3 beta PS integrin in border cell migration and in stretch cells. Developmental Dynamics 237:3927-3939, 2008. (c) 2008 Wiley-Liss, Inc.