CNRS, VetAgro Sup, UMR 5558, Laboratoire de Biométrie et Biologie Évolutive, Universite Lyon 1, Villeurbanne, France.
IZInovation, 13 Rue des Émeraudes, Lyon 69006, France.
Genome Biol Evol. 2024 Aug 5;16(8). doi: 10.1093/gbe/evae158.
The common bed bug, Cimex lectularius, is one of the main human parasites. The world-wide resurgence of this pest is mainly due to globalization, and the spread of insecticide resistance. A few studies have compared the transcriptomes of susceptible and resistant strains; however, these studies usually relied on strains originating from distant locations, possibly explaining their extended candidate gene lists. Here, we compared the transcriptomes of 2 strains originating from the same location and showing low overall genetic differentiation (FST=0.018) but varying in their susceptibility to pyrethroids, before and after insecticide exposure. In sharp contrast with previous studies, only 24 genes showing constitutive differential expression between the strains were identified. Interestingly, most of the genes with increased expression in the resistant strain encoded cuticular proteins. However, those changes were not associated with significant difference in cuticular thickness, suggesting that they might be involved in qualitative changes in the cuticle. In contrast, insecticide exposure induced the expression of a multitude of genes, mostly involved in detoxification. Finally, our set of transcriptome candidate loci showed little overlap with a set of loci strongly genetically differentiated in a previous study using the same strains. Several hypothesis explaining this discrepancy are discussed.
常见的臭虫，Cimex lectularius，是主要的人类寄生虫之一。这种害虫在世界范围内的死灰复燃主要是由于全球化和杀虫剂耐药性的传播。有一些研究比较了敏感和耐药菌株的转录组；然而，这些研究通常依赖于来自不同地点的菌株，这可能解释了它们扩展的候选基因列表。在这里，我们比较了来自同一地点的 2 个菌株的转录组，这两个菌株在对拟除虫菊酯的敏感性方面表现出低总体遗传分化（FST=0.018），但在暴露于杀虫剂前后表现出不同的敏感性。与以前的研究形成鲜明对比的是，只鉴定出了 24 个在菌株之间表现出组成型差异表达的基因。有趣的是，耐药菌株中大多数表达增加的基因编码表皮蛋白。然而，这些变化与表皮厚度没有显著差异相关，表明它们可能参与了表皮的定性变化。相比之下，杀虫剂暴露诱导了大量基因的表达，这些基因主要参与解毒。最后，我们的转录组候选基因座集与之前使用相同菌株的一项研究中强烈遗传分化的基因座集几乎没有重叠。讨论了几种解释这种差异的假设。
