Expression of the immediate-early gene-encoded protein Egr-1 (zif268) during in vitro classical conditioning.
Expression of the immediate-early genes (IEGs) has been shown to be induced by activity-dependent synaptic plasticity or behavioral training and is thought to play an important role in long-term memory. In the present study, we examined the induction and expression of the IEG-encoded protein Egr-1 during an in vitro neural correlate of eyeblink classical conditioning. The results showed that Egr-1 protein expression as determined by immunocytochemistry and Western blot analysis rapidly increased during the early stages of conditioning and remained elevated during the later stages. Further, expression of Egr-1 protein required NMDA receptor activation as it was blocked by bath application of AP-5. These findings suggest that the IEG-encoded proteins such as Egr-1 are activated during relatively simple forms of learning in vertebrates. In this case, Egr-1 may have a functional role in the acquisition phase of conditioning as well as in maintaining expression of conditioned responses.
Mokin
Maxim
M
Neuroscience Group, Division of Basic Biomedical Sciences, University of South Dakota School of Medicine, Vermillion, South Dakota 57069, USA.
Keifer
Joyce
J
D000818:Animals; D001245:Association Learning / Q000502:physiology*; D001933:Brain Stem / Q000378:metabolism*; D003056:Cochlear Nerve / Q000502:physiology; D003214:Conditioning, Classical / Q000502:physiology*; D003215:Conditioning, Eyelid / Q000502:physiology; D004268:DNA-Binding Proteins / Q000378:metabolism*; D051766:Early Growth Response Protein 1; D004558:Electric Stimulation; D017874:Immediate-Early Proteins / Q000378:metabolism*; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D014276:Trigeminal Nerve / Q000502:physiology; D014426:Turtles
D004268:DNA-Binding Proteins; D051766:Early Growth Response Protein 1; D017874:Immediate-Early Proteins; D016194:Receptors, N-Methyl-D-Aspartate; D014157:Transcription Factors