Light- and focus-dependent expression of the transcription factor ZENK in the chick retina

Nat Neurosci. 1999 Aug;2(8):706-12. doi: 10.1038/11167.


Ocular growth and refraction are regulated by visual processing in the retina. We identified candidate regulatory neurons by immunocytochemistry for immediate-early gene products, ZENK (zif268, Egr-1) and Fos, after appropriate visual stimulation. ZENK synthesis was enhanced by conditions that suppress ocular elongation (plus defocus, termination of form deprivation) and suppressed by conditions that enhance ocular elongation (minus defocus, form deprivation), particularly in glucagon-containing amacrine cells. Fos synthesis was enhanced by termination of visual deprivation, but not by defocus and not in glucagon-containing amacrine cells. We conclude that glucagon-containing amacrine cells respond differentially to the sign of defocus and may mediate lens-induced changes in ocular growth and refraction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Ocular*
  • Animals
  • Chickens
  • DNA-Binding Proteins / genetics*
  • Gene Expression Regulation / physiology
  • Gene Expression Regulation / radiation effects*
  • Immediate-Early Proteins / genetics*
  • Immunohistochemistry
  • Light*
  • Male
  • Neurons / physiology
  • Neurons / radiation effects
  • Proto-Oncogene Proteins c-fos / genetics
  • Receptors, N-Methyl-D-Aspartate / drug effects
  • Receptors, N-Methyl-D-Aspartate / physiology
  • Retina / cytology
  • Retina / metabolism
  • Retina / radiation effects*
  • Transcription Factors / genetics*


  • DNA-Binding Proteins
  • Immediate-Early Proteins
  • Proto-Oncogene Proteins c-fos
  • Receptors, N-Methyl-D-Aspartate
  • Transcription Factors