Dauer constitutive (Daf-c) mutants of C. elegans have been extensively studied as a model to understand the regulatory molecules involved in organismal development and longivity. Recently one of the longevity extending factor, insulin/IGF-1 receptor mutant Daf-2 have been reported to have enhanced learning and memory. To elucidate this further, we tested butanone-associated appetitive learning in insulin mutant
ins-1 and found enhanced learning in this strain similar to that of Daf-2. However,
daf-16,
akt-1 and
age-1 mutants did not show a significant reduction in learning, suggesting the limited involvement of Daf-2 downstream pathways in learning and memory. Surprisingly, associative-learning in post-dauer N2 strains showed a significant reduction in learning and memory paradigm compared to the control wild-type adults. Furthermore, 24-hour starved worms also showed significantly low learning and memory. These results suggest that the learning deficiency could be linked to the environment or epigenetic factors during early development of an organism. Besides, AWC sensory neuron, which is known to express the insulin receptor Daf-2 might have a regulatory role in integrating various cues to determine the learning and memory capabilities of the organism.