Skip to main content
Dryad logo

Interaction of field realistic doses of clothianidin and Varroa destructor parasitism on adult honey bee (Apis mellifera L.) health and neural gene expression, and antagonistic effects on differentially expressed genes

Citation

Morfin, Nuria; Goodwin, Paul H.; Guzman-Novoa, Ernesto (2021), Interaction of field realistic doses of clothianidin and Varroa destructor parasitism on adult honey bee (Apis mellifera L.) health and neural gene expression, and antagonistic effects on differentially expressed genes , Dryad, Dataset, https://doi.org/10.5061/dryad.9w0vt4bbg

Abstract

While many studies have examined the effects of neonicotinoid insecticides and the parasitic mite Varroa destructor on honey bees (Apis mellifera), more information on the combined effects of such stressors on gene expression, including neural related genes, and their impact on biological pathways is needed. This study analyzed the effects of field realistic concentrations of the neonicotinoid clothianidin on adult bees infested and not infested with Vdestructor over 21 consecutive days and then determined bee survivorship, weight, deformed wing virus (DWV) levels and gene expression. Vdestructor parasitism with or without clothianidin exposure was significantly associated with decreased survivorship, weight loss and higher DWV levels, while clothianidin exposure was only associated with higher levels of DWV. Expression analysis of the neural genes AmNlg-1BlCh and AmAChE-2 showed that Vdestructor caused a significant down-regulation of all of them, whereas clothianidin caused a significant down-regulation of only AmNrx-1 and BlCh. An interaction was only detected for AmNrx-1 expression. RNAseq analysis showed that clothianidin exposure resulted in 6.5 times more up-regulated differentially expressed genes (DEGs) than Vdestructor alone and 123 times more than clothianidin combined with Vdestructor. Similar results were obtained with down-regulated DEGs, except for a higher number of DEGs shared between Vdestructor and the combined stressors. KEGG (Kyoto Encyclopedia of Genes and Genomes) biological pathway analysis of the DEGs showed that the stressor linked to the highest number of KEGG pathways was clothianidin, followed by Vdestructor, and then considerably fewer number of KEGG pathways with the combined stressors. The reduced numbers of DEGs and KEGG pathways associated with the DEGs for the combined stressors compared to the stressors alone indicates that the interaction of the stressors is not additive or synergistic, but antagonistic. The possible implications of the antagonistic effect on the number of DEGs are discussed.

Methods

The description of the collection of the data is described in the research article Morfin N, Goodwin PH, Guzman-Novoa E. Interaction of field realistic doses of clothianidin and Varroa destructor parasitism on adult honey bee (Apis mellifera L.) health and neural gene expression, and antagonistic effects on differentially expressed genes. PloS ONE. 2020 Feb 20;15(2):e0229030.

Funding

Agricultural Research Institute of Ontario

Ontario Ministry of Agriculture, Food and Rural Affairs

The Pinchin Family

Agricultural Research Institute of Ontario

The Pinchin Family