Regulated and polarized PtdIns(3,4,5)P3 accumulation is essential for apical membrane morphogenesis in photoreceptor epithelial cells.

Background: In a specialized epithelial cell such as the Drosophila photoreceptor, a conserved set of proteins is essential for the establishment of polarity, its maintenance, or both--in Drosophila, these proteins include the apical factors Bazooka, D-atypical protein kinase C, and D-Par6 together with D-Ecadherin. However, little is known about the mechanisms by which such apical factors might regulate the differentiation of the apical membrane into functional domains such as an apical-most stack of microvilli or more lateral sub-apical membrane.

Results: We show that in photoreceptors Bazooka (D-Par3) recruits the tumor suppressor lipid phosphatase PTEN to developing cell-cell junctions (Zonula Adherens, za).