Recombinant Human NMNAT-2 Protein, CF

Humans produce three nicotinamide mononucleotide adenylyltransferase (NMNAT) enzymes. All three enzymes transfer adenylate from ATP to nicotinamide ribonucleotide or nicotinate ribonucleotide to generate NAD⁺ or deamido-NAD⁺, and are important enzymes in the NAD biosynthetic pathway (1). The three enzymes differ in tissue expression patterns and subcellular location, indicating that they each play a unique role in NAD homeostasis (2). NMNAT-2 is expressed primarily in the central nervous system and in muscle tissue in contrast to NMNAT-1, which has a broad tissue distribution (3). NMNAT-2 is found in the cytosol and Golgi complex, while NMNAT-1 is a nuclear enzyme and NMNAT-3 is mitochondrial (1). A number of studies have implicated the NMNAT proteins in cancer and neurodegenerative diseases (4). NMNAT‑2 has been shown to be essential for the maintenance of healthy axons. When the level of this labile protein falls below a critical threshold in axons, the process of axonal degeneration begins (5). The axon-protective function of NMNAT-2 is dependent on its NAD⁺ synthesis activity (6).