title: Expression of collapsin response mediator proteins in the nervous system of embryonic zebrafish.
abstract: Collapsin response mediator proteins (CRMPs also known as TUC, Drp, Ulip, TOAD-64) are cytosolic phosphoproteins that are involved in signal transduction during axon growth and in cytoskeletal dynamics. Here we report cloning and mRNA expression patterns of CRMP-1, -2, -3, -4 and, owing to a genome duplication in teleosts, two homologs of CRMP-5 (CRMP-5a and -5b) in embryonic zebrafish at 16 and 24h post-fertilization (hpf). CRMPs are evolutionarily conserved and zebrafish CRMPs show amino acid identities of 76-90% with their homologs in humans, with the exception of CRMP-3, which shows only 67% homology. Between 16 and 24hpf, expression of CRMPs generally increased in many regions of the CNS undergoing neuronal differentiation and axonogenesis, but not in the proliferative ventricular zone. Structures that were typically labeled by most, but not all the CRMP probes were the telencephalon, the nucleus of the tract of the post-optic commissure, the epiphysis, the nucleus of the medial longitudinal fascicle, clusters of hindbrain neurons, cranial ganglia, as well as Rohon-Beard neurons. No expression of CRMP mRNAs was observed outside the nervous system. Thus, expression patterns of different CRMP family members correlate with neuronal differentiation and axonogenesis in embryonic zebrafish.
authors.affiliation: Zentrum für Molekulare Neurobiologie, Universität Hamburg, Martinistr. 52, D-20246 Hamburg, Germany.
authors.forename: Jörn
authors.initials: J
authors.lastname: Schweitzer
authors.forename: Catherina G
authors.initials: CG
authors.lastname: Becker
authors.forename: Melitta
authors.initials: M
authors.lastname: Schachner
authors.forename: Thomas
authors.initials: T
authors.lastname: Becker
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017124:Conserved Sequence; D004625:Embryo, Nonmammalian / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009024:Morphogenesis; D009419:Nerve Tissue Proteins / Q000235:genetics; D009420:Nervous System / Q000196:embryology*; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics; D040121:Semaphorin-3A / Q000502:physiology*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D015027:Zebrafish / Q000196:embryology*; D029961:Zebrafish Proteins / Q000502:physiology
chemical_list: C405926:Dpysl4 protein, mouse; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D040121:Semaphorin-3A; D029961:Zebrafish Proteins