N-Acetylaspartylglutamate (NAAG) is found at high concentrations in the vertebrate nervous system. It is an agonist of group II metabotropic glutamate receptors. A number of other functions have been proposed for NAAG, including a role as a non-excitotoxic transport form of glutamate and a molecular water pump (Lodder-Gadaczek et al. 2011, Neale et al. 2011).
NAAG is synthesized by N-acetylaspartylglutamate synthase A (RIMKLA, NAAG synthetase A) and Beta-citrylglutamate synthase B (RIMKLB, NAAG synthetase B), which more efficiently catalyzes the synthesis of beta-citryl-L-glutamate (Collard et al. 2010, Lodder-Gadaczek et al. 2011).
Van Schaftingen, E
N-acetyl-L-aspartate-L-glutamate ligase activity of RIMKLA, RIMKLB [cytosol]