title: Proteomic analysis revealed a novel synaptic proline-rich membrane protein (PRR7) associated with PSD-95 and NMDA receptor.
abstract: Proteomic analyses have revealed a novel synaptic proline-rich membrane protein: PRR7 (proline rich 7), in the postsynaptic density (PSD) fraction of rat forebrain. PRR7 is 269 amino acid residues long, and displays a unique architecture, composed of a very short N-terminal extracellular region, a single membrane spanning domain, and a cytoplasmic domain possessing a proline-rich sequence and a C-terminal type-1 PDZ binding motif. A fraction of PRR7 accumulates in spines along with synapse maturation, and colocalizes with PSD-95 in a punctate pattern in rat hippocampal neural cultures. Immunoprecipitation and GST pull-down assays demonstrated that PRR7 binds to the third PDZ domain of PSD-95. In addition, the NMDA receptor subunits, NR1 and NR2B, specifically co-immunoprecipitated with PRR7. These results suggest that PRR7 is involved in modulating neural activities via interactions with the NMDA receptor and PSD-95, and PSD core formation.
authors.affiliation: Department of Biophysics, Graduate School of Science, Kyoto University, Oiwake, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Murata
authors.forename: Tomoko
authors.initials: T
authors.lastname: Doi
authors.forename: Hisaaki
authors.initials: H
authors.lastname: Taniguchi
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Fujiyoshi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000276:immunology; D000915:Antibody Affinity; D001921:Brain / Q000166:cytology / Q000378:metabolism; D002478:Cells, Cultured; D003902:Detergents / Q000494:pharmacology; D000076122:Disks Large Homolog 4 Protein; D020869:Gene Expression Profiling; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism; D006801:Humans; D047468:Immunoprecipitation; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D040901:Proteomics; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D016415:Sequence Alignment; D012995:Solubility / Q000187:drug effects; D014020:Tissue Extracts
chemical_list: D000906:Antibodies; D003902:Detergents; D000076122:Disks Large Homolog 4 Protein; C501449:Dlg4 protein, rat; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C409466:NR1 NMDA receptor; C121001:NR2B NMDA receptor; D009419:Nerve Tissue Proteins; C497335:PRR7 protein, rat; D016194:Receptors, N-Methyl-D-Aspartate; D014020:Tissue Extracts; C033652:postsynaptic density proteins