Rabggtb, Geranylgeranyl transferase type-2 subunit beta
Enzyme Classification 18.104.22.168
Also Known as
PGTB2_RAT, Rabggtb, Ggtb
Catalyzes the transfer of a geranylgeranyl moiety from geranylgeranyl diphosphate to both cysteines of Rab proteins with the C-terminal sequence -XXCC, -XCXC and -CCXX, such as RAB1A, RAB3A, RAB5A and RAB7A. Heterotrimer composed of RABGGTA, RABGGTB and CHM; within this trimer, RABGGTA and RABGGTB form the catalytic component B, while CHM (component A) mediates peptide substrate binding. The Rab GGTase dimer (RGGT) interacts with CHM (component A) prior to Rab protein binding; the association is stabilized by geranylgeranyl pyrophosphate (GGpp). The CHM:RGGT:Rab complex is destabilized by GGpp. Interaction of RABGGTB with prenylated PTP4A2 precludes its association with RABGGTA and inhibits enzyme activity. Interacts with CHODL.