BACKGROUND: SAPAP1 was originally identified as a protein interacting with the guanylate kinase domain of PSD-95. SAPAP1 also interacts with various proteins, including neurofilaments, synaptic scaffolding molecule (S-SCAM), nArgBP2, dynein light chain and Shank through different regions. RESULTS: We expressed various regions of SAPAP1 in hippocampal neurones. The synaptic targeting of SAPAP1 was mediated by the N-terminal region and did not depend on the interaction with PSD-95 or S-SCAM. SAPAP1 was not involved in the synaptic localization of PSD-95 or S-SCAM, but affected that of Shank. The synaptic targeting of SAPAP1 was not suppressed by blocking NMDA or AMPA receptors. Fluorescent recovery after a photobleaching study revealed that SAPAP1 was immobile at synapses. CONCLUSION: SAPAP1 is a component of the static core of PSD, and its dynamics are different from those of the other PSD components, PSD-95, S-SCAM and BEGAIN.

This article has been cited by other articles:

				S. Kalla, M. Stern, J. Basu, F. Varoqueaux, K. Reim, C. Rosenmund, N. E. Ziv, and N. Brose Molecular Dynamics of a Presynaptic Active Zone Protein Studied in Munc13-1-Enhanced Yellow Fluorescent Protein Knock-In Mutant Mice J. Neurosci., December 13, 2006; 26(50): 13054 - 13066. [Abstract] [Full Text] [PDF]

				T. Kuriu, A. Inoue, H. Bito, K. Sobue, and S. Okabe Differential control of postsynaptic density scaffolds via actin-dependent and -independent mechanisms. J. Neurosci., July 19, 2006; 26(29): 7693 - 7706. [Abstract] [Full Text] [PDF]

				S. Romorini, G. Piccoli, M. Jiang, P. Grossano, N. Tonna, M. Passafaro, M. Zhang, and C. Sala A Functional Role of Postsynaptic Density-95-Guanylate Kinase-Associated Protein Complex in Regulating Shank Assembly and Stability to Synapses J. Neurosci., October 20, 2004; 24(42): 9391 - 9404. [Abstract] [Full Text] [PDF]