Adapter protein that regulates intracellular membrane fusion reactions (By similarity) (PubMed:33725482). Regulates the fusion of lysosome-related organelles (PubMed:33725482). Promotes microtubules nucleation and centrosomal recruitment of microtubule nucleating proteins such as msps (PubMed:33725482). In syncytial embryos, during the formation of yolk granules, suppresses vesicle fusion events with lipid droplets, possibly via interaction with Rab5 (PubMed:33725482). In the eye, regulates pigment granules size (PubMed:22934826). In hemocytes, required for the late steps of bacteria phagocytosis (PubMed:22934826). In fat body, required for autophagosome maturation (PubMed:22934826). Interacts with Rab5; the interaction is independent of GDP or GTP (PubMed:33725482). Interacts with msps (PubMed:33725482). Associated to yolk granules during vitellogenesis. Expressed in follicular epithelial cells on the side facing the developing oocyte where yolk components are secreted before uptake into the oocyte (at protein level) (PubMed:33725482). Expressed in syncytial embryos (at protein level) (PubMed:33725482).