title: Laminin peptide YIGSR and its receptor regulate sensory axonal response to the chemoattractive guidance cue in the chick embryo.
abstract: During early development, centrally projecting dorsal root ganglion (DRG) neurons extend their axons toward the dorsal spinal cord. We previously reported the involvement of dorsal spinal cord-derived chemoattraction in this projection (Masuda et al. [ 2007] Neuroreport 18:1645-1649). However, the molecular nature of this attraction is not clear. Here we show that laminin-1 (alpha1beta1gamma1) is expressed strongly along the pathway of DRG axons and that its 67-kDa receptor (67LR) is present on DRG cells. This evidence suggests that laminin-1-67LR signaling may be involved in DRG axonal guidance. By employing culture assays, we show that laminin-1 or the YIGSR peptide, a soluble peptide of the laminin beta1 chain, promotes the DRG axonal response to dorsal spinal cord-derived chemoattraction. By using a function-blocking antibody against 67LR, we show that the anti-67LR antibody blocks the modulation of DRG axonal response by the YIGSR peptide in vitro. Furthermore, the in ovo injection of the anti-67LR antibody inhibits the DRG axonal growth toward the dorsal spinal cord. These results provide evidence that the YIGSR peptide promotes dorsal spinal cord-derived chemoattraction via 67LR to contribute to the formation of the initial trajectories of developing DRG axons.
authors.affiliation: Department of Anatomy, Fukushima Medical University School of Medicine, Fukushima, Japan. tmasu@fmu.ac.jp
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Masuda
authors.forename: Chie
authors.initials: C
authors.lastname: Sakuma
authors.forename: Kenta
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Kikuchi
authors.forename: Emi
authors.initials: E
authors.lastname: Soda
authors.forename: Takashi
authors.initials: T
authors.lastname: Shiga
authors.forename: Kazuto
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yaginuma
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism*; D002630:Chemotactic Factors / Q000378:metabolism; D002642:Chick Embryo; D005727:Ganglia, Spinal / Q000254:growth & development*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007797:Laminin / Q000378:metabolism; D009414:Nerve Growth Factors / Q000378:metabolism*; D009842:Oligopeptides / Q000378:metabolism*; D017474:Receptors, Laminin / Q000378:metabolism*; D011984:Sensory Receptor Cells / Q000166:cytology / Q000378:metabolism*
chemical_list: D002630:Chemotactic Factors; D007797:Laminin; D009414:Nerve Growth Factors; D009842:Oligopeptides; D017474:Receptors, Laminin; C121346:laminin 1; C081571:tyrosyl-isoleucyl-glycyl-seryl-arginine