Odor experiences during preimaginal stages cause behavioral and neural plasticity in adult honeybees

G.P. RAMÍREZ; J. P. GROSSO; W.M. FARINA; P ARGIBAY; C. B. FAGUNDEZ; A. ARENAS

Frontiers in Behavioral Neuroscience

Frontiers

Año: 2016 vol. 10

In eusocial insects, experiences acquired during the development have long-termconsequences on mature behavior. In the honeybee that suffers profound changesassociated with metamorphosis, the effect of odor experiences at larval instars onthe subsequent physiological and behavioral response is still unclear. To address theimpact of preimaginal experiences on the adult honeybee, colonies containing larvaewere fed scented food. The effect of the preimaginal experiences with the food odorwas assessed in learning performance, memory retention and generalization in 3?5-and 17?19 day-old bees, in the regulation of their expression of synaptic-related genesand in the perception and morphology of their antennae. Three-five day old bees thatexperienced 1-hexanol (1-HEX) as food scent responded more to the presentationof the odor during the 1-HEX conditioning than control bees (i.e., bees reared incolonies fed unscented food). Higher levels of proboscis extension response (PER) to1-HEX in this group also extended to HEXA, the most perceptually similar odor to theexperienced one that we tested. These results were not observed for the group testedat older ages. In the brain of young adults, larval experiences triggered similar levelsof neurexins (NRXs) and neuroligins (Nlgs) expression, two proteins that have beeninvolved in synaptic formation after associative learning. At the sensory periphery, theexperience did not alter the number of the olfactory sensilla placoidea, but did reducethe electrical response of the antennae to the experienced and novel odor. Our studyprovides a new insight into the effects of preimaginal experiences in the honeybeeand the mechanisms underlying olfactory plasticity at larval stage of holometabolousinsects.