title: Eph family transmembrane ligands can mediate repulsive guidance of trunk neural crest migration and motor axon outgrowth.
abstract: In vertebrate embryos, neural crest cell migration and motor axon outgrowth are restricted to rostral somite halves by repulsive factors located in the caudal somite compartment. We show that two Eph family transmembrane ligands, Lerk2 and HtkL, are expressed in caudal somite halves, and that crest cells and motor axons express receptors for these ligands. In several independent in vitro assays, preclustered ligand-Fc fusion proteins can repulsively guide both crest migration and motor axon outgrowth. These repulsive activities depend on a graded or discontinuous presentation of the ligands when tested in the context of permissive substrates, such as laminin or fibronectin. These results identify Lerk2 and HtkL as potential determinants of segmental pattern in the peripheral nervous system.
authors.affiliation: Division of Biology, California Institute of Technology, Pasadena 91125, USA.
authors.forename: H U
authors.initials: HU
authors.lastname: Wang
authors.forename: D J
authors.initials: DJ
authors.lastname: Anderson
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology*; D002465:Cell Movement / Q000502:physiology; D002633:Chemotaxis; D036387:Ephrin-B1; D036388:Ephrin-B2; D005353:Fibronectins; D006801:Humans; D007797:Laminin; D008024:Ligands; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D009024:Morphogenesis; D009046:Motor Neurons / Q000502:physiology*; D005810:Multigene Family; D009420:Nervous System / Q000196:embryology; D009432:Neural Crest / Q000166:cytology*; D009924:Organ Culture Techniques; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics / Q000502:physiology*; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism / Q000502:physiology; D019170:Somites / Q000166:cytology*
chemical_list: D036387:Ephrin-B1; D036388:Ephrin-B2; D005353:Fibronectins; D007797:Laminin; D008024:Ligands; D008565:Membrane Proteins; D011506:Proteins; D011993:Recombinant Fusion Proteins