title: Characterization of zebrafish PSD-95 gene family members.
abstract: The PSD-95 family of membrane- associated guanylate kinases (MAGUKs) are thought to act as molecular scaffolds that regulate the assembly and function of the multiprotein signaling complex found at the postsynaptic density of excitatory synapses. Genetic analysis of PSD-95 family members in the mammalian nervous system has so far been difficult, but the zebrafish is emerging as an ideal vertebrate system for studying the role of particular genes in the developing and mature nervous system. Here we describe the cloning of the zebrafish orthologs of PSD-95, PSD-93, and two isoforms of SAP-97. Using in situ hybridization analysis we show that these zebrafish MAGUKs have overlapping but distinct patterns of expression in the developing nervous system and craniofacial skeleton. Using a pan-MAGUK antibody we show that MAGUK proteins localize to neurons within the developing hindbrain, cerebellum, visual and olfactory systems, and to skin epithelial cells. In the olfactory and visual systems MAGUK proteins are expressed strongly in synaptic regions, and the onset of expression in these areas coincides with periods of synapse formation. These data are consistent with the idea that PSD-95 family members are involved in synapse assembly and function, and provide a platform for future functional studies in vivo in a highly tractable model organism.
authors.affiliation: Department of Molecular and Cellular Physiology, Beckman Center, Stanford University, California 94305, USA. martinm@stanford.edu
authors.forename: Martin P
authors.initials: MP
authors.lastname: Meyer
authors.forename: James S
authors.initials: JS
authors.lastname: Trimmer
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Gilthorpe
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Smith
mesh_terms: D000818:Animals; D015153:Blotting, Western / Q000379:methods; D019556:COS Cells; D002522:Chlorocebus aethiops; D003001:Cloning, Molecular / Q000379:methods; D006224:Cricetinae; D000076122:Disks Large Homolog 4 Protein; D004622:Embryo, Mammalian; D004625:Embryo, Nonmammalian; D015870:Gene Expression / Q000502:physiology; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D051528:Guanylate Kinases; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D017403:In Situ Hybridization / Q000379:methods; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D051379:Mice; D009419:Nerve Tissue Proteins / Q000145:classification / Q000235:genetics* / Q000502:physiology; D009420:Nervous System / Q000254:growth & development / Q000378:metabolism; D009703:Nucleoside-Phosphate Kinase / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D051381:Rats; D049231:Saposins / Q000378:metabolism; D016415:Sequence Alignment / Q000379:methods; D015027:Zebrafish
chemical_list: D000076122:Disks Large Homolog 4 Protein; C501447:Dlg4 protein, mouse; C501449:Dlg4 protein, rat; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C501451:Mpp2 protein, rat; D009419:Nerve Tissue Proteins; D049231:Saposins; C033652:postsynaptic density proteins; D009703:Nucleoside-Phosphate Kinase; C501445:Dlg2 protein, mouse; D051528:Guanylate Kinases