Component of the biogenesis of lysosome-related organelles complex-1 (BLOC-1) involved in gut granule biogenesis. Homodimer (isoform 1). Component of the biogenesis of lysosome-related organelles complex-1 (BLOC-1) composed at least of blos-1, blos-2, blos-4, dsbn-1, glo-2, mutd-1 and snpn-1 (By similarity). Isoform 1 interacts with blos-1 and blos-4. Expressed in developing embryos in intestinal cells (at protein level). Belongs to the BLOC1S6 family.