Olfactory associative learning in Caenorhabditis elegans is impaired in lrn-1 and lrn-2 mutants.
The C. elegans mutants, lrn-1 and lrn-2, are impaired in associative learning using conditioned taste cues. Both mutants are defective in associative learning about appetitive and aversive events, indicating that lrn-1 and lrn-2 exert effects across motivational boundaries. In a new olfactory associative learning paradigm, in which wild type worms learn to avoid a previously attractive diacetyl odor after it has been paired with an aversive acetic acid solution, lrn-1 and lrn-2 are impaired. Although defective in associative learning using a conditioned olfactory cue, nonassociative learning (habituation and dishabituation) using this same olfactory cue is unaffected. The discovery that lrn-1 and lrn-2 are defective in associative learning with both taste and olfactory cues may suggest that associative learning in different sensory modalities converges on a common genetic pathway in C. elegans that is subserved by lrn-1 and lrn-2.
Morrison
G E
GE
Department of Anatomy and Cell Biology, University of Toronto, Ontario, Canada. g.morrison@utoronto.ca
Wen
J Y
JY
Runciman
S
S
van der Kooy
D
D
D000818:Animals; D001245:Association Learning / Q000502:physiology*; D017173:Caenorhabditis elegans / Q000235:genetics*; D002633:Chemotaxis; D003214:Conditioning, Classical; D005108:Extinction, Psychological; D006185:Habituation, Psychophysiologic; D009154:Mutation / Q000235:genetics*; D018034:Olfactory Receptor Neurons / Q000502:physiology*