The axonal glycoprotein TAG-1 is an immunoglobulin superfamily member with neurite outgrowth-promoting activity

Cell. 1990 Apr 6;61(1):157-70. doi: 10.1016/0092-8674(90)90223-2.


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.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Axons / immunology
  • Axons / physiology*
  • Base Sequence
  • Cell Adhesion Molecules, Neuronal / genetics
  • Cell Line
  • Cerebellum / embryology
  • Cerebellum / immunology
  • Contactin 2
  • DNA / genetics
  • DNA / isolation & purification
  • Gene Library
  • Genes, Immunoglobulin*
  • Genetic Vectors
  • Membrane Glycoproteins / genetics*
  • Molecular Sequence Data
  • Multigene Family*
  • Neurons
  • Nucleic Acid Hybridization
  • Protein Conformation
  • RNA, Messenger / genetics
  • Rats
  • Receptors, Antigen, B-Cell / genetics*
  • Sequence Homology, Nucleic Acid
  • Spinal Cord / embryology
  • Spinal Cord / immunology
  • Transfection


  • Cell Adhesion Molecules, Neuronal
  • Cntn2 protein, rat
  • Contactin 2
  • Membrane Glycoproteins
  • RNA, Messenger
  • Receptors, Antigen, B-Cell
  • DNA

Associated data

  • GENBANK/M31725