This gene encodes a lysosomal protein that interacts with RAB7, a small GTPase that controls transport to endocytic degradative compartments. Studies using mutant forms of the two proteins suggest that this protein represents a downstream effector for RAB7, and both proteins act together in the regulation of late endocytic traffic. A unique region of this protein has also been shown to be involved in the regulation of lysosomal morphology. [provided by RefSeq, Sep 2011].