With NUS1, forms the dehydrodolichyl diphosphate synthase (DDS) complex, an essential component of the dolichol monophosphate (Dol-P) biosynthetic machinery. Both subunits contribute to enzymatic activity, i.e. condensation of multiple copies of isopentenyl pyrophosphate (IPP) to farnesyl pyrophosphate (FPP) to produce dehydrodolichyl diphosphate (Dedol-PP), a precursor of dolichol phosphate which is utilized as a sugar carrier in protein glycosylation in the endoplasmic reticulum (ER) . Synthesizes long-chain polyprenols, mostly of C95 and C100 chain length . Regulates the glycosylation and stability of nascent NPC2, thereby promoting trafficking of LDL-derived cholesterol .
Endoplasmic reticulum membrane ; Peripheral membrane protein . colocalizes with calnexin.
Expressed at high levels in testis and kidney. Expressed in epididymis (at protein level). Slightly expressed in heart, spleen and thymus.