IMPDH (肌苷-磷酸脱氢酶)

IMPDH is a purine biosynthetic enzyme that catalyzes the conversion of inosine 5'-monophosphate (IMP) to xanthosine 5'-monophosphate (XMP). This is the rate-limiting step in the de novo biosynthesis of guanine nucleotides (GMP), and the reaction requires the coenzyme nicotinamide adenine dinucleotide (NAD⁺). There are mainly two subtypes of IMPDH, IMPDH1 and IMPDH2. IMPDH is a regulator of the intracellular guanine nucleotide pool, and is therefore important for DNA and RNA synthesis, signal transduction, energy transfer, glycoprotein synthesis, as well as other process that are involved in cellular proliferation. In addition, IMPDH can regulate the activation and proliferation of lymphocytes and affect the immune response. The abnormal expression of IMPDH is closely related to cancer and autoimmune diseases^[1][2].