School of Biological and Chemical Sciences, Queen Mary University of London, London, UK.
School of Biological, Earth and Environmental Sciences, University College Cork, Cork, Ireland.
Mol Ecol. 2019 Apr;28(8):1964-1974. doi: 10.1111/mec.15047. Epub 2019 Mar 6.
Social bees are important insect pollinators of wildflowers and agricultural crops, making their reported declines a global concern. A major factor implicated in these declines is the widespread use of neonicotinoid pesticides. Indeed, recent research has demonstrated that exposure to low doses of these neurotoxic pesticides impairs bee behaviours important for colony function and survival. However, our understanding of the molecular-genetic pathways that lead to such effects is limited, as is our knowledge of how effects may differ between colony members. To understand what genes and pathways are affected by exposure of bumblebee workers and queens to neonicotinoid pesticides, we implemented a transcriptome-wide gene expression study. We chronically exposed Bombus terrestriscolonies to either clothianidin or imidacloprid at field-realistic concentrations while controlling for factors including colony social environment and worker age. We reveal that genes involved in important biological processes including mitochondrial function are differentially expressed in response to neonicotinoid exposure. Additionally, clothianidin exposure had stronger effects on gene expression amplitude and alternative splicing than imidacloprid. Finally, exposure affected workers more strongly than queens. Our work demonstrates how RNA-Seq transcriptome profiling can provide detailed novel insight on the mechanisms mediating pesticide toxicity to a key insect pollinator.
社会性蜜蜂是野生花卉和农作物的重要传粉昆虫，它们数量的减少引起了全球关注。导致这些蜜蜂减少的一个主要因素是新烟碱类杀虫剂的广泛使用。事实上，最近的研究表明，接触这些神经毒性杀虫剂的低剂量会损害对蜂群功能和生存至关重要的蜜蜂行为。然而，我们对导致这些影响的分子遗传途径的了解是有限的，我们也不知道这些影响在蜂群成员之间可能有何不同。为了了解接触新烟碱类杀虫剂对熊蜂工蜂和蜂王的基因和途径有何影响，我们进行了全转录组基因表达研究。我们以田间实际浓度慢性暴露于噻虫啉或吡虫啉的 B. terrestris 群体，同时控制包括群体社会环境和工蜂年龄在内的因素。我们发现，与新烟碱类杀虫剂暴露相关的基因参与了重要的生物学过程，包括线粒体功能。此外，与吡虫啉相比，噻虫啉暴露对基因表达幅度和选择性剪接的影响更强。最后，暴露对工蜂的影响比对蜂王更强。我们的工作表明，RNA-Seq 转录组谱分析如何为关键传粉昆虫的农药毒性的介导机制提供详细的新见解。
