DLG1, also called synapse-associated protein 97 (SAP97), is a scaffolding protein that clusters at synapses and plays an important role in synaptic development and plasticity. DLG1 plays roles in regulating cell polarity, proliferation, migration, and cycle progression. It interacts with AMPA-type glutamate receptors and is critical in their maturation and delivery to synapses. It also interacts with PKCalpha and promotes wound healing. DLG1 is a member of the MAGUK (membrane-associated guanylate kinase) protein family, which is characterized by the presence of a core of three domains: PDZ, SH3, and guanylate kinase (GuK). The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. DLG1 contains three PDZ domains. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.
Comment:The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain.
Jiyao W et al.(2023). "The conserved domain database in 2023.",