title: The axonal glycoprotein TAG-1 is an immunoglobulin superfamily member with neurite outgrowth-promoting activity.
abstract: Pathfinding of axons in the developing nervous system is thought to be mediated by glycoproteins expressed on the surface of embryonic axons and growth cones. One molecule suggested to play a role in axonal growth is TAG-1, a 135 kd glycoprotein expressed transiently on the surface of subsets of neurons in the developing mammalian nervous system. We isolated a full-length cDNA clone encoding rat TAG-1. TAG-1 has six immunoglobulin-like domains and four fibronectin type III-like repeats and is structurally similar to other immunoglobulin-like proteins expressed on developing axons. Neurons maintained in vitro on a substrate of TAG-1 extend long neurites, suggesting that this protein plays a role in the initial growth and guidance of axons in vivo. TAG-1 is anchored to the neuronal membrane via a glycosyl phosphatidylinositol linkage and is also released from neurons, suggesting that TAG-1 also functions as a substrate adhesion molecule when released into the extracellular environment.
authors.affiliation: Department of Biochemistry and Molecular Biophysics, New York, New York.
authors.forename: A J
authors.initials: AJ
authors.lastname: Furley
authors.forename: S B
authors.initials: SB
authors.lastname: Morton
authors.forename: D
authors.initials: D
authors.lastname: Manalo
authors.forename: D
authors.initials: D
authors.lastname: Karagogeos
authors.forename: J
authors.initials: J
authors.lastname: Dodd
authors.forename: T M
authors.initials: TM
authors.lastname: Jessell
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001369:Axons / Q000276:immunology / Q000502:physiology*; D001483:Base Sequence; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics; D002460:Cell Line; D002531:Cerebellum / Q000196:embryology / Q000276:immunology; D058969:Contactin 2; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D015723:Gene Library; D005803:Genes, Immunoglobulin; D005822:Genetic Vectors; D008562:Membrane Glycoproteins / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family; D009474:Neurons; D009693:Nucleic Acid Hybridization; D011487:Protein Conformation; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D011947:Receptors, Antigen, B-Cell / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D013116:Spinal Cord / Q000196:embryology / Q000276:immunology; D014162:Transfection
chemical_list: D015816:Cell Adhesion Molecules, Neuronal; C548676:Cntn2 protein, rat; D058969:Contactin 2; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D011947:Receptors, Antigen, B-Cell; D004247:DNA