Inosine-5'-Monophosphate Dehydrogenase 1 (IMPDH1)

IMP dehydrogenase 1 acts as a homotetramer to regulate cell growth. IMPDH1 is an enzyme that catalyzes the synthesis of xanthine monophosphate (XMP) from inosine-5'-monophosphate (IMP). This is the rate-limiting step in the de novo synthesis of guanine nucleotides.

The sequence of these clones demonstrated an open reading frame for a protein containing 514 amino acids. The molecular mass of the produced protein was 56 kD, which is the observed molecular mass of the purified protein and of the immunoprecipitated in vitro translation product. A high order of conservation of the IMP dehydrogenase protein was indicated by the finding that human and Chinese hamster cDNA clones differed by only 8 amino acids.