| First Author | Kim E | Year | 1997 |
| Journal | J Cell Biol | Volume | 136 |
| Issue | 3 | Pages | 669-78 |
| PubMed ID | 9024696 | Mgi Jnum | J:53164 |
| Mgi Id | MGI:1331349 | Doi | 10.1083/jcb.136.3.669 |
| Citation | Kim E, et al. (1997) GKAP, a novel synaptic protein that interacts with the guanylate kinase-like domain of the PSD-95/SAP90 family of channel clustering molecules. J Cell Biol 136(3):669-78 |
| abstractText | The molecular mechanisms underlying the organization of ion channels and signaling molecules at the synaptic junction are largely unknown. Recently, members of the PSD-95/SAP90 family of synaptic MAGUK (membrane-associated guanylate kinase) proteins have been shown to interact, via their NH2-terminal PDZ domains, with certain ion channels (NMDA receptors and K+ channels), thereby promoting the clustering of these proteins. Although the function of the NH2-terminal PDZ domains is relatively well characterized, the function of the Src homology 3 (SH3) domain and the guanylate kinase-like (GK) domain in the COOH-terminal half of PSD-95 has remained obscure. We now report the isolation of a novel synaptic protein, termed GKAP for guanylate kinase- associated protein, that binds directly to the GK domain of the four known members of the mammalian PSD-95 family. GKAP shows a unique domain structure and appears to be a major constituent of the postsynaptic density. GKAP colocalizes and coimmunoprecipitates with PSD-95 in vivo, and coclusters with PSD-95 and K+ channels/NMDA receptors in heterologous cells. Given their apparent lack of guanylate kinase enzymatic activity, the fact that the GK domain can act as a site for protein-protein interaction has implications for the function of diverse GK-containing proteins (such as p55, ZO-1, and LIN-2/CASK). |
