SAP102/A0016

Synapse-associated protein 102 (SAP102 or A0016) is a scaffold protein that belongs to the membrane-associated guanylate kinase (MAGUK) family (PSD93, PSD95, SAP97, SAP102).

Synapse-associated protein 102 (SAP102 or A0016) is a scaffold protein that belongs to the membrane-associated guanylate kinase (MAGUK) family (PSD93, PSD95, SAP97, SAP102). The protein is highly expressed in neuronal and endocrine tissues. In the brain, SAP102 is expressed during early development and it is localized in the post-synaptic density (PSD) structure in excitatory synapses. The predicted 849 amino acid sequence contains three PDZ domains, a SH3 domain, and a guanylate kinase-homology domain. SAP102 directly binds the NR2 subunits of the N-methyl-D-aspartate receptor (NMDAR) and other proteins responsible for NMDAR localization, trafficking and signaling. SAP102 knock-out mice showed an impaired synaptic plasticity as well as a deficit in NMDAR-dependent spatial learning. The human gene maps to the chromosome position Xq13.1. Truncating mutations in the human SAP102 cause X-linked mental retardation.