TAG-1-deficient mice have marked elevation of adenosine A1 receptors in the hippocampus

Biochem Biophys Res Commun. 2001 Feb 16;281(1):220-6. doi: 10.1006/bbrc.2001.4334.


TAG-1 is a neural recognition molecule in the immunoglobulin superfamily that is predominantly expressed in the developing brain. Several lines of evidence suggest that TAG-1 is involved in the outgrowth, guidance, and fasciculation of neurites. To directly assess the function of TAG-1 in vivo, we have generated mice with a deletion in the gene encoding TAG-1 using homologous recombination in embryonic stem cells. Gross morphological analysis of the cerebellum, the spinal cord, and the hippocampus appeared normal in TAG-1-deficient mice. However, TAG-1 (-/-) mice showed the upregulation of the adenosine A1 receptors determined by [(3)H]cyclopentyl-1,3-dipropylxanthine in the hippocampus, and their greater sensitivity to convulsant stimuli than that in TAG-1 (+/+) mice. We suspect that the subtle changes in neural plasticity induced by TAG-1 deficiency during development cause the selective vulnerability of specific brain regions and the epileptogenicity in TAG-1 (-/-) mice.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies / metabolism
  • Blotting, Southern
  • Blotting, Western
  • Cell Adhesion
  • Cell Adhesion Molecules, Neuronal*
  • Cerebellum / metabolism
  • Contactin 2
  • Embryo, Mammalian / metabolism
  • Gene Deletion
  • Hippocampus / metabolism*
  • Immunohistochemistry
  • Membrane Glycoproteins / genetics*
  • Membrane Glycoproteins / physiology*
  • Mice
  • Mice, Knockout
  • Models, Genetic
  • Mutagenesis, Site-Directed
  • Rabbits
  • Receptors, Purinergic P1 / biosynthesis*
  • Recombination, Genetic
  • Seizures / genetics
  • Spinal Cord / metabolism
  • Stem Cells / metabolism
  • Up-Regulation


  • Antibodies
  • Cell Adhesion Molecules, Neuronal
  • Cntn2 protein, mouse
  • Contactin 2
  • Membrane Glycoproteins
  • Receptors, Purinergic P1