Component of the BLOC-1 complex, a complex that is required for normal biogenesis of lysosome-related organelles (LRO). May also participate in the coupling of lysosomes to microtubule plus-end-directed kinesin motor. May also play a role in intracellular vesicle trafficking. May negatively regulate aerobic respiration through mitochondrial protein lysine-acetylation. Component of the biogenesis of lysosome-related organelles complex 1 (BLOC-1). Belongs to the BLOC1S1 family.