A heterodimeric complex that functions as a GTPase-Activating Protein (GAP) Complex for members of the Rag family of GTPases. In the budding yeast, this complex contains Lst4 and Lst7, while the orthologous mammalian complex contains follicular (FLCN) and either follicular interacting protein 1 (FNIP1) or FNIP2.
Catalysis of the reaction: 2 3-acyl-sn-glycero-1-phospho-(1'-sn-glycerol) = 3-acyl-sn-glycero-1-phospho-(3'-acyl-1'-sn-glycerol) + sn-glycero-1-phospho-(1'-sn-glycerol).
Catalysis of the synthesis of the HKK-1 carbohydrate epitope; adds a sulfate group to a precursor, GlcA-beta-(1->3)-Gal-beta-(1->4)-GlcNAc-beta-(1->R), forming sulfo-3GlcA-beta-(1->3)-Gal-beta-(1->4)-GlcNAc-beta-(1->R).