This gene encodes a protein containing a potential clathrin-binding motif, consensus dileucine signals, and tyrosine-based sorting signals for targeting to vesicles of lysosomal lineage. The encoded protein may play a role in organelle biogenesis associated with melanosomes, platelet dense granules, and lysosomes. Mutations in this gene are associated with Hermansky-Pudlak syndrome type 3. Alternate splice variants exist, but their full length sequence has not been determined. [provided by RefSeq, Jul 2008]