Gripap, Grasp, GRIP1-associated protein

GRASP (GRP1-associated scaffold protein, tamalin) is a 395 amino acid proteinencoded by the human gene GRASP . GRASP is a scaffold protein that com-prises multiple protein-interacting domains, including a 95kD postsynaptic density protein (PSD-95)/discs-large/ZO-1 (PDZ) domain, a leucine-zipperregion and a carboxyl-terminal PDZ-binding motif. GRASP is involved with intracellular trafficking and contributes to the macromolecular organization of group 1 metabotropic glutamate receptors (mGluRs) at synapses. GRASP forms a heteromer composed of GRASP , PSCD2 and at least one mGluR-1. It also interacts with PSCD3, mGluR-2, mGluR-3 and mGluR-5. GRASP is highly expressed in brain and has lower levels of expression in lung, heart, embryo, kidney and ovary. Kitano, J., Kimura, K., Yamazaki, Y., Soda, T., Shigemoto, R., Nakajima, Y.and Nakanishi, S. 2002. Tamalin, J. Neurosci. 22: 280-1289. Hall, B.S., Gabernet-Castello, C., Voak, A., Goulding, D., Natesan, S.K. and Field, M.C. 2006. J. Biol. Chem. 281: 27600-27612. Sugi, T., Oyama, T., Muto, T., Nakanishi, S., Morikawa, K. and Jingami, H. 2007. Crystal structures of autoinhibitory PDZ domain of Tamalin EMBO J.26: 2192-2205.