Catalyzes the trans-addition of the three molecules of IPP onto DMAPP to form geranylgeranyl pyrophosphate, an important precursor of carotenoids and geranylated proteins.
Subcellular locations: Cytoplasm, Cytoplasm, Perinuclear region, Cytoplasm, Myofibril, Sarcomere, Z line
Abundantly expressed in testis (, ). Found in other tissues to a lower extent (, ). Expressed in dermal fibroblast and skeletal muscle .