Topographic restriction of TAG-1 expression in the developing retinotectal pathway and target dependent reexpression during axon regeneration

Mol Cell Neurosci. 2001 Feb;17(2):398-414. doi: 10.1006/mcne.2000.0936.

Abstract

TAG-1, a glycosylphosphatidyl inositol (GPI)-anchored protein of the immunoglobulin (Ig) superfamily, exhibits an unusual spatiotemporal expression pattern in the fish visual pathway. Using in situ hybridization and new antibodies (Abs) against fish TAG-1 we show that TAG-1 mRNA and anti-TAG-1 staining is restricted to nasal retinal ganglion cells (RGCs) in 24- to 72-h-old zebrafish embryos and in the adult, continuously growing goldfish retina. Anti-TAG-1 Abs selectively label nasal RGC axons in the nerve, optic tract, and tectum. Axotomized RGCs reexpress TAG-1, which occurs as late as 12 days after optic nerve lesion, when regenerating RGC axons arrive in the tectum, suggesting TAG-1 reexpression is target contact-dependent. Accordingly, TAG-1 reexpression ceases upon interruption of the regenerating projection by a second lesion. The topographic restriction of TAG-1 expression and its target dependency during regeneration suggests that TAG-1 might play a role in the retinotopic organization and restoration of the retinotectal pathway.

Publication types

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

MeSH terms

  • Animals
  • Axons / chemistry
  • Axons / physiology*
  • Cell Adhesion Molecules, Neuronal*
  • Contactin 2
  • Gene Expression Regulation, Developmental
  • Goldfish
  • Membrane Glycoproteins / analysis
  • Membrane Glycoproteins / genetics*
  • Nerve Regeneration / physiology*
  • Optic Nerve / cytology
  • Optic Nerve / embryology
  • Optic Nerve / physiology
  • Optic Nerve Injuries
  • RNA, Messenger / analysis
  • Retinal Ganglion Cells / chemistry
  • Retinal Ganglion Cells / cytology
  • Retinal Ganglion Cells / physiology*
  • Superior Colliculi / cytology
  • Superior Colliculi / embryology
  • Zebrafish

Substances

  • Cell Adhesion Molecules, Neuronal
  • Contactin 2
  • Membrane Glycoproteins
  • RNA, Messenger