Component of the biogenesis of lysosome-related organelles complex-1 (BLOC-1) involved in pigment granule biogenesis. Component of the biogenesis of lysosome-related organelles complex-1 (BLOC-1) composed of Blos1, Blos2, Blos3, Blos4, Dysb, Muted, Pldn and Snapin. Belongs to the BLOC1S5 family.