Anti-HPS4 antibodies are used in the immunodetection of the protein HPS4 biogenesis of lysosomal organelles complex 3 subunit 2. In humans, the canonical protein has a reported length of 708 amino acid residues and a mass of 76.9 kDa. Up to 4 different isoforms have been reported for this protein. It is notably widely expressed in many tissue types. HPS4 is a known component of the BLOC-3 complex, a complex that acts as a guanine exchange factor (GEF) for RAB32 and RAB38, promotes the exchange of GDP to GTP, converting them from an inactive GDP-bound form into an active GTP-bound form. The HPS4 gene has been associated with the disease, Hermansky-Pudlak syndrome. Synonyms for this target antigen include BLOC-3 complex member HPS4 and light-ear protein homolog. HPS4 gene orthologs have been reported in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species. Some HPS4 antibodies may have been used in research and have associated citations. Western Blot is a widely used application for these antibodies. Immunocytochemistry and Immunofluorescence are also common applications.