MAGUK protein

Cai C, Li H, Rivera C, Keinanen K. 2006. Interaction between SAP97 and PSD-95, two Maguk proteins involved in synaptic trafficking of AMPA receptors. J Biol Chem 281 4267-4273. 

Table 2. Distribution of PDZ domain-containing proteins in neuronal multiprotein complexes. As MAGUK proteins and other PDZ domain-containing proteins provide important scaffolding functions in protein complexes their distribution was analysed. The most widely used PDZ domain-containing proteins are DLGH3 and SAP97. The differential use of these proteins in complexes containing subtypes of 5-HT receptor highlights the heterogeneity and variability in complexes even in closely related receptors...

The list of proteins that can interact with the cytoplasmic tail of NMDA receptor subunits is growing. Here we discuss a few examples that were not mentioned in earlier sections. S-SCAM, a protein with an N-terminal GK domain followed by two WW motifs and five PDZ domains, has been shown to bind to NR2 subunits with its fifth PDZ domain (Hirao et al., 1998). S-SCAM belongs to a family of proteins that includes AIPl and MAGI, which are distantly related to the MAGUK proteins. MALS, a mammalian homolog of LIN-7, can also bind to NR2 subunits via a PDZ-C-terminus interaction (Jo et al., 1999). The significance of these interactions for NMDA receptor function in vivo remains to be determined. 

Haskins J, Gu L, Wittchen ES, Hibbard J, Stevenson BR. ZO-3, a novel member of the MAGUK protein family found at the tight junction, interacts with ZO-1 and occludin. J Cell Biol 1998 141 199-208. 

Neuroligin is a protein that binds to the PDZs of PSD95. Neuroligin reaches into the synaptic cleft and interacts with [3-neurexin, a protein that reaches into the synaptic cleft from the presynaptic side P-neurexin is anchored presynaptically to the PDZ domain of another MAGUK, CASK. This arrangement connects the pre-and postsynaptic elements and stabilizes the synapse mechanically. 

The first of the four zones includes the postsynaptic membrane and approximately the upper half of the PSD. In this zone, preferential labeling is seen for all ionotropic glutamate receptors and for the associated proteins known as membrane-associated guanylate kinases (MAGUKs) including PSD-95, SAP-102, PSD-93, and SAP-97 (Valtschanoff et al., 1999) (Figs. 7 and 8). The second zone includes approximately the bottom half (for the purpose... 

PSD-95/S AP90 belongs to the MAGUK superfamily of proteins, which are characterized by the presence of PDZ domains, an SH3 domain and a guanylate kinase-like (GK) domain (Cho et al., 1992 Kistner et al., 1993). PDZ domains are modular protein domains of 90 amino acids that are specialized for binding to C-terminal peptides in a sequence-specific... 

Dimitratos, S. D. Woods, D. F. et al. (1999). "Signaling pathways are focused at specialized regions of the plasma membrane by scaffolding proteins of the MAGUK family." Bioessays, 21(11), 912-21. 

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