title: Neuronal and non-neuronal collapsin-1 binding sites in developing chick are distinct from other semaphorin binding sites.
abstract: The collapsin and semaphorin family of extracellular proteins contributes to axonal path finding by repulsing axons and collapsing growth cones. To explore the mechanism of collapsin-1 action, we expressed and purified a truncated collapsin-1-alkaline phosphatase fusion protein (CAP-4). This protein retains biological activity as a DRG growth cone collapsing agent and saturably binds to DRG neurons with low nanomolar affinity. Specific CAP-4 binding sites are present on DRG neurons, sympathetic neurons, and motoneurons, but not on retinal, cortical, or brainstem neurons. Outside the nervous system, high levels of CAP-4 binding sites are present in the mesenchyme surrounding major blood vessels and developing bone and in lung. These sites provide a substrate for the collapsin-1-dependent patterning of non-neuronal tissues perturbed in sema III (-/-) mice. The staining patterns for mouse semaphorin D/III and chick collapsin-1 fusion proteins are indistinguishable from one another but quite separate from that for semaphorin B and M-semaphorin F fusion proteins. These data imply that a family of high-affinity semaphorin binding sites similar in complexity to the semaphorin ligand family exists.
authors.affiliation: Department of Neurology, Yale University, New Haven, Connecticut 06520, USA.
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: F
authors.initials: F
authors.lastname: Nakamura
authors.forename: S M
authors.initials: SM
authors.lastname: Strittmatter
mesh_terms: D000818:Animals; D030161:Avian Proteins; D001369:Axons / Q000187:drug effects; D001665:Binding Sites; D002478:Cells, Cultured; D002490:Central Nervous System / Q000166:cytology / Q000378:metabolism; D002642:Chick Embryo; D018076:DNA, Complementary / Q000235:genetics; D005326:Fetal Proteins / Q000378:metabolism; D005727:Ganglia, Spinal / Q000166:cytology / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism*; D008168:Lung / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008648:Mesoderm / Q000378:metabolism; D051379:Mice; D009046:Motor Neurons / Q000378:metabolism; D005810:Multigene Family; D009414:Nerve Growth Factors / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D020933:Neurotrophin 3; D009928:Organ Specificity; D051381:Rats; D017207:Rats, Sprague-Dawley; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D040121:Semaphorin-3A
chemical_list: D030161:Avian Proteins; D018076:DNA, Complementary; D005326:Fetal Proteins; D006023:Glycoproteins; D008565:Membrane Proteins; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; D020933:Neurotrophin 3; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins; D040121:Semaphorin-3A; C109241:collapsin-1 receptor, Gallus gallus