nicotinamide mononucleotide adenylyltransferase 2; NMN adenylyltransferase 2; nicotinate-nucleotide adenylyltransferase 2; NaMN adenylyltransferase 2 (NMNAT2, C1orf15, KIAA0479)

Function

• NAD+ biosynthesis

ATP + nicotinamide ribonucleotide  <-->  diphosphate + NAD+

Cofactor:

• divalent metal cations
• Mg+2 confers the highest activity

Kinetic parameters:

• KM=32 uM for NMN
• KM=70 uM for NAD+
• KM=204 uM for ATP
• KM=1119 uM for PPi
• KM=14.5 uM for NaMN
• KM=304 uM for NMNH
• Vmax=1.1 umol/min/mg enzyme for NAD synthesis
• Vmax=3 umol/min/mg enzyme for pyrophosphorolytic NAD+ cleavage
• Vmax=7 umol/min/mg enzyme for pyrophosphorolytic NADH cleavage
• - KM is >100 uM for triazofurin monophosphate
• pH dependence: optimum pH is 6.0-9.0

Structure

• belongs to the eukaryotic NMN adenylyltransferase family

Compartment

cytoplasm

Alternative splicing

named isoforms=2

Expression

• highly expressed in brain, including cerebrum, cerebellum, occipital lobe, frontal lobe, temporal lobe, putamen
• detected at lower levels in heart, skeletal muscle
• detected in pancreas, islets of Langerhans

More general terms

• nicotinamide mononucleotide adenylyltransferase

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=23057
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:23057
• OMIM: https://mirror.omim.org/entry/608701
• UniProt: http://www.uniprot.org/uniprot/Q9BZQ4.html