Rab effector playing a role in late endocytic transport to degradative compartments (PubMed:11179213, PubMed:11696325, PubMed:12944476, PubMed:14668488, PubMed:27113757). Involved in the regulation of lysosomal morphology and distribution (PubMed:14668488, PubMed:27113757). Induces recruitment of dynein-dynactin motor complexes to Rab7A-containing late endosome and lysosome compartments (PubMed:11179213, PubMed:11696325). Promotes centripetal migration of phagosomes and the fusion of phagosomes with the late endosomes and lysosomes (PubMed:12944476).