title: Effect of a thymol application on olfactory memory and gene expression levels in the brain of the honeybee Apis mellifera.
abstract: Essential oils are used by beekeepers to control the Varroa mites that infest honeybee colonies. So, bees can be exposed to thymol formulations in the hive. The effects of the monoterpenoid thymol were explored on olfactory memory and gene expression in the brain of the honeybee. In bees previously exposed to thymol (10 or 100 ng/bee), the specificity of the response to the conditioned stimulus (CS) was lost 24 h after learning. Besides, the octopamine receptor OA1 gene Amoa1 showed a significant decrease of expression 3 h after exposure with 10 or 100 ng/bee of thymol. With the same doses, expression of Rdl gene, coding for a GABA receptor subunit, was not significantly modified but the trpl gene was upregulated 1 and 24 h after exposure to thymol. These data indicated that the genes coding for the cellular targets of thymol could be rapidly regulated after exposure to this molecule. Memory and sensory processes should be investigated in bees after chronic exposure in the hive to thymol-based preparations.
authors.affiliation: VAcBio Group, EA 4357, Champollion University Center, 81012, Albi Cedex 09, France.
authors.forename: Elsa
authors.initials: E
authors.lastname: Bonnafé
authors.forename: Florian
authors.initials: F
authors.lastname: Drouard
authors.forename: Lucie
authors.initials: L
authors.lastname: Hotier
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Carayon
authors.forename: Pierre
authors.initials: P
authors.lastname: Marty
authors.forename: Michel
authors.initials: M
authors.lastname: Treilhou
authors.forename: Catherine
authors.initials: C
authors.lastname: Armengaud
mesh_terms: D056810:Acaricides / Q000009:adverse effects*; D000818:Animals; D001483:Base Sequence; D001516:Bees / Q000187:drug effects / Q000502:physiology*; D001921:Brain / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects*; D008568:Memory / Q000187:drug effects*; D008969:Molecular Sequence Data; D060888:Real-Time Polymerase Chain Reaction; D017982:Receptors, Biogenic Amine / Q000378:metabolism; D011963:Receptors, GABA-A / Q000378:metabolism; D012903:Smell / Q000187:drug effects*; D018709:Statistics, Nonparametric; D013943:Thymol / Q000009:adverse effects*; D050051:Transient Receptor Potential Channels / Q000235:genetics / Q000378:metabolism
chemical_list: D056810:Acaricides; D017931:DNA Primers; D017982:Receptors, Biogenic Amine; D011963:Receptors, GABA-A; D050051:Transient Receptor Potential Channels; C027604:norsynephrine receptor; D013943:Thymol