Immunity related genes in honey bees in response to synthetic acaricidal treatments.

GARRIDO, P. MELISA; ANTÚNEZ K.; MARTÍN M.L.; PORRINI M. P.; EGUARAS M, J.

Buenos Aires

Encuentro; 45th Annual Meeting of the Society for Invertebrate Pathology; 2012

Society for Invertebrate Pathology

The mite Varroa destructor is an ectoparasiteaffecting honey bees worldwide, causing serious economic damage on beekeeping. Syntheticacaricides have been among the principal tools available tobeekeepers for varroa management. Several studies have been shown its negative effects on honey beephysiology even at sub-lethal levels. Recent researchsuggests that those molecules strongly impact on immune signaling cascades andcellular immunity. However, toxicitystudies at immune gene expression levels are few. In the presentwork, LC50 in six-day-old bees weredetermined for the following acaricides: tau-fluvalinate, flumethrin, amitrazand coumaphos. According to this obtainedvalue, a group of individuals were treated and then processed for qt-PCRanalysis. Transcript levels for the genes encoding theantimicrobial proteins hymenoptaecin and defensin, the immunity related proteinsphenoloxidase and vitellogenin were assessed.Flumethrin significantly elevated the expression of hymenoptaecin andphenoloxidase. With respect defensin expression, differences became significantwhen coumaphos vs. flumethrin treated bees were compared, although nodifferences were detected when comparison was made with control bees. Nosignificant changes were recorded in the expression levels of vitellogeninamong bees treated with acaricides and control bees. This work constitutes thefirst report, under laboratory conditions, about induction of immune related genes in response tosynthetic miticides. We discuss possible underlying mechanisms for theseresults and host susceptibility to different pathogens after acaricide exposure,since some of these molecules frequently have been found in apiculturalmatrices at high concentrations.