Synaptic localization of SAPAP1, a synaptic membrane-associated protein.
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.


CONCLUSIONS
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.
Yao
Ikuko
I
Department of Medical Biochemistry, Graduate School of Medicine, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
Iida
Junko
J
Nishimura
Wataru
W
Hata
Yutaka
Y
D000818:Animals; D001665:Binding Sites; D019556:COS Cells; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D049452:Green Fluorescent Proteins; D006624:Hippocampus / Q000166:cytology; D008164:Luminescent Proteins / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D016900:Neurofilament Proteins / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D051381:Rats; D000074407:SAP90-PSD95 Associated Proteins; D013569:Synapses / Q000378:metabolism*
D002352:Carrier Proteins; D008164:Luminescent Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D016900:Neurofilament Proteins; D016271:Proto-Oncogene Proteins c-myc; D000074407:SAP90-PSD95 Associated Proteins; D049452:Green Fluorescent Proteins