title: Defining the ligand specificity of the deleted in colorectal cancer (DCC) receptor.
abstract: The growth and guidance of many axons in the developing nervous system require Netrin-mediated activation of Deleted in Colorectal Cancer (DCC) and other still unknown signaling cues. Commissural axon guidance defects are more severe in DCC mutant mice than Netrin-1 mutant mice, suggesting additional DCC activating signals besides Netrin-1 are involved in proper axon growth. Here we report that interaction screens on extracellular protein microarrays representing over 1,000 proteins uniquely identified Cerebellin 4 (CBLN4), a member of the C1q-tumor necrosis factor (TNF) family, and Netrin-1 as extracellular DCC-binding partners. Immunofluorescence and radio-ligand binding studies demonstrate that Netrin-1 competes with CBLN4 binding at an overlapping site within the membrane-proximal fibronectin domains (FN) 4-6 of DCC and binds with ∼5-fold higher affinity. CBLN4 also binds to the DCC homolog, Neogenin-1 (NEO1), but with a lower affinity compared to DCC. CBLN4-null mice did not show a defect in commissural axons of the developing spinal cord but did display a transient increase in the number of wandering axons in the brachial plexus, consistent with a role in axon guidance. Overall, the data solidifies CBLN4 as a bona fide DCC ligand and strengthens its implication in axon guidance.
authors.affiliation: Department of Neuroscience, Genentech, South San Francisco, California, United States of America.
authors.forename: Patrick C G
authors.initials: PC
authors.lastname: Haddick
authors.affiliation: Department of Protein Chemistry, Genentech, South San Francisco, California, United States of America.
authors.forename: Irene
authors.initials: I
authors.lastname: Tom
authors.affiliation: Department of Protein Chemistry, Genentech, South San Francisco, California, United States of America.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Luis
authors.affiliation: Department of Protein Chemistry, Genentech, South San Francisco, California, United States of America.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Quiñones
authors.affiliation: Department of Protein Chemistry, Genentech, South San Francisco, California, United States of America.
authors.forename: Bernd J
authors.initials: BJ
authors.lastname: Wranik
authors.affiliation: Department of Protein Chemistry, Genentech, South San Francisco, California, United States of America.
authors.forename: Sree R
authors.initials: SR
authors.lastname: Ramani
authors.affiliation: Department of Protein Chemistry, Genentech, South San Francisco, California, United States of America.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Stephan
authors.affiliation: Department of Neuroscience, Genentech, South San Francisco, California, United States of America.
authors.forename: Marc
authors.initials: M
authors.lastname: Tessier-Lavigne
authors.affiliation: Department of Protein Chemistry, Genentech, South San Francisco, California, United States of America.
authors.forename: Lino C
authors.initials: LC
authors.lastname: Gonzalez
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism; D002352:Carrier Proteins; D000075389:DCC Receptor; D047108:Embryonic Development / Q000235:genetics; D006801:Humans; D007700:Kinetics; D008024:Ligands; D051379:Mice; D009154:Mutation; D009414:Nerve Growth Factors / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D000075388:Netrin-1; D055495:Neurogenesis / Q000235:genetics; D009474:Neurons / Q000378:metabolism; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D025941:Protein Interaction Mapping; D011498:Protein Precursors / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D025521:Tumor Suppressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D000075389:DCC Receptor; C501909:DCC protein, human; D008024:Ligands; C000617351:NTN1 protein, human; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; C000617353:Ntn1 protein, mouse; D011498:Protein Precursors; D011956:Receptors, Cell Surface; D025521:Tumor Suppressor Proteins; C542343:cerebellin 4 precursor, mouse; D000075388:Netrin-1