Nicotinamide Nucleotide Adenylyltransferase 2 (NMNAT2)

NMNAT2 belongs to the nicotinamide mononucleotide adenylyltransferase (NMNAT) enzyme family, members of which catalyze an essential step in NAD (NADP) biosynthetic pathway. Unlike the other human family member, which is localized to the nucleus, and is ubiquitously expressed; this enzyme is cytoplasmic, and is predominantly expressed in the brain. Two transcript variants encoding different isoforms have been found for this gene.The deduced 307-amino acid protein has a calculated molecular mass of 34.4 kD. NMNAT1 contains 2 conserved NMNAT signature sequences, both of which include an ATP-binding site and are considered essential for catalytic activity. It lacks the first 157 N-terminal amino acids of the yeast NMNATs, and it lacks the nuclear localization signal found in NMNAT1.