Description
This gene encodes the rate-limiting enzyme in the de novo guanine nucleotide biosynthesis. It is thus involved in maintaining cellular guanine deoxy- and ribonucleotide pools needed for DNA and RNA synthesis. The encoded protein catalyzes the NAD-dependent oxidation of inosine-5′-monophosphate into xanthine-5′-monophosphate, which is then converted into guanosine-5′-monophosphate. This gene is up-regulated in some neoplasms, suggesting it may play a role in malignant transformation.