CBGP, INRAE, CIRAD, IRD, Montpellier SupAgro, Univ Montpellier, Montpellier, France.
Départment de Biologie Animale, Faculté des Sciences et Techniques, Université Cheikh Anta Diop (UCAD), Fann, Dakar, Senegal.
Sci Rep. 2020 Oct 26;10(1):18257. doi: 10.1038/s41598-020-75060-2.
Biological invasions are major anthropogenic changes associated with threats to biodiversity and health. However, what determines the successful establishment and spread of introduced populations remains unclear. Here, we explore several hypotheses linking invasion success and immune phenotype traits, including those based on the evolution of increased competitive ability concept. We compared gene expression profiles between anciently and recently established populations of two major invading species, the house mouse Mus musculus domesticus and the black rat Rattus rattus, in Senegal (West Africa). Transcriptome analyses identified differential expression between anciently and recently established populations for 364 mouse genes and 83 rat genes. All immune-related genes displaying differential expression along the mouse invasion route were overexpressed at three of the four recently invaded sites studied. Complement activation pathway genes were overrepresented among these genes. By contrast, no particular immunological process was found to be overrepresented among the differentially expressed genes of black rat. Changes in transcriptome profiles were thus observed along invasion routes, but with different specific patterns between the two invasive species. These changes may be driven by increases in infection risks at sites recently invaded by the house mouse, and by stochastic events associated with colonization history for the black rat. These results constitute a first step toward the identification of immune eco-evolutionary processes potentially involved in the invasion success of these two rodent species.
生物入侵是与生物多样性和健康威胁相关的主要人为变化。然而，引入种群成功建立和传播的决定因素仍不清楚。在这里，我们探讨了将入侵成功与免疫表型特征联系起来的几种假设，包括基于竞争能力增强进化概念的假设。我们比较了塞内加尔（西非）两个主要入侵物种，家鼠 Mus musculus domesticus 和黑鼠 Rattus rattus 的古老和新近建立种群之间的基因表达谱。转录组分析确定了 364 个小鼠基因和 83 个大鼠基因在古老和新近建立的种群之间存在差异表达。沿着老鼠入侵路线显示差异表达的所有与免疫相关的基因在研究的四个最近入侵地点中的三个地点均过度表达。补体激活途径基因在这些基因中过度表达。相比之下，在黑鼠的差异表达基因中没有发现特定的免疫过程过度表达。因此，在入侵路线上观察到了转录组图谱的变化，但两种入侵物种之间存在不同的特定模式。这些变化可能是由家鼠最近入侵地点感染风险的增加以及黑鼠的定居历史相关的随机事件驱动的。这些结果是确定这两个啮齿动物物种入侵成功中可能涉及的免疫生态进化过程的第一步。
