BLOC-1 or biogenesis of lysosome-related organelles complex 1 is a ubiquitously expressed multisubunit protein complex. BLOC-1 is required for normal biogenesis of specialized organelles of the endosomal-lysosomal system, such as melanosomes and platelet dense granules. The complex was first described in 2004.
The identified protein subunits of BLOC-1 include: