Integrin alpha-PS3/beta-PS is a receptor for laminin. Also binds to wb. Important during embryogenesis for the development of the trachea, dorsal vessel and salivary gland, as well as for dorsal closure. Required for short-term memory processes. Minor involvement in the establishment of the oocyte anterior-posterior length. Plays a role in timely border cell migration during oogenesis, probably mediated by JNK signaling. Integrin alpha-PS3/Itgbn is required for effective phagocytosis of apoptotic cells during embryonic development and for the phagocytic elimination of S.aureus by mediating the binding of S.aureus peptidoglycan to larval hemocytes, which probably activates a signaling pathway involving Rac1 and Rac2. Integrin alpha-PS3/Itgbn also regulates Fak activity during neuromuscular junction (NMJ) growth and is required for its activation in presynapsis of NMJs. Seems to be dispensable for major morphogenetic processes. Heterodimer of an alpha and a beta subunit. The alpha subunit is composed of a heavy and a light chain linked by a disulfide bond. Interacts with mys/beta-PS and Itgbn. Apical membrane localization in primordial dorsal-appendage cells at oogenesis stages 10B and 11. Later, weakly expressed in lateral membrane of cells surrounding the outgrowing dorsal appendages. Expressed in embryonic and larval hemocytes (at protein level). Expressed in tissues undergoing invagination, tissue movement and morphogenesis such as salivary gland, trachea, midgut endoderm, dorsal vessel, midline of the ventral nerve cord, amnioserosa and the amnioproctodeal invagination. Expressed in the mushroom body neuropil, brain areas that contain mushroom body processes in synaptic contact with other neurons. In egg chambers, expressed in border cells, in stretch cells and in dorsal appendage primordia. Expressed throughout development. Highest expression is observed in pupae (at protein level). During oogenesis, expressed from stage 10B onwards. Flies display impaired olfactory memories within 3 min of training. Mutant embryos show reduced level of phagocytosis. Belongs to the integrin alpha chain family.