Viljakainen Lumi, Fürst Matthias A, Grasse Anna V, Jurvansuu Jaana, Oh Jinook, Tolonen Lassi, Eder Thomas, Rattei Thomas, Cremer Sylvia
Ecology and Genetics Research Unit, University of Oulu, Oulu, Finland.
Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria.
Front Microbiol. 2023 Mar 16;14:1119002. doi: 10.3389/fmicb.2023.1119002. eCollection 2023.
Hosts can carry many viruses in their bodies, but not all of them cause disease. We studied ants as a social host to determine both their overall viral repertoire and the subset of actively infecting viruses across natural populations of three subfamilies: the Argentine ant (, Dolichoderinae), the invasive garden ant (, Formicinae) and the red ant (, Myrmicinae). We used a dual sequencing strategy to reconstruct complete virus genomes by RNA-seq and to simultaneously determine the small interfering RNAs (siRNAs) by small RNA sequencing (sRNA-seq), which constitute the host antiviral RNAi immune response. This approach led to the discovery of 41 novel viruses in ants and revealed a host ant-specific RNAi response (21 vs. 22 nt siRNAs) in the different ant species. The efficiency of the RNAi response (sRNA/RNA read count ratio) depended on the virus and the respective ant species, but not its population. Overall, we found the highest virus abundance and diversity per population in , followed by and . Argentine ants also shared a high proportion of viruses between populations, whilst overlap was nearly absent in . Only one of the 59 viruses was found to infect two of the ant species as hosts, revealing high host-specificity in active infections. In contrast, six viruses actively infected one ant species, but were found as contaminants only in the others. Disentangling spillover of disease-causing infection from non-infecting contamination across species is providing relevant information for disease ecology and ecosystem management.
宿主体内可携带多种病毒，但并非所有病毒都会引发疾病。我们将蚂蚁作为一种社会性宿主进行研究，以确定其整体病毒库以及在三个亚科的自然种群中活跃感染病毒的子集，这三个亚科分别是：阿根廷蚁（Dolichoderinae亚科）、入侵花园蚁（Formicinae亚科）和红蚁（Myrmicinae亚科）。我们采用了双重测序策略，通过RNA测序（RNA-seq）重建完整的病毒基因组，并通过小RNA测序（sRNA-seq）同时确定构成宿主抗病毒RNA干扰（RNAi）免疫反应的小干扰RNA（siRNA）。这种方法促使我们在蚂蚁中发现了41种新型病毒，并揭示了不同蚂蚁物种中宿主蚂蚁特异性的RNAi反应（21 nt与22 nt的siRNA）。RNAi反应的效率（sRNA/RNA读数计数比）取决于病毒和相应的蚂蚁物种，而非其种群。总体而言，我们发现[未提及的蚂蚁种类1]中每个种群的病毒丰度和多样性最高，其次是[未提及的蚂蚁种类2]和[未提及的蚂蚁种类3]。阿根廷蚁种群之间也共享了高比例的病毒，而[未提及的蚂蚁种类3]中几乎不存在重叠。在59种病毒中，只有一种被发现可感染两种蚂蚁物种作为宿主，这表明活跃感染中具有高度的宿主特异性。相比之下，有六种病毒活跃感染一种蚂蚁物种，但仅在其他蚂蚁物种中作为污染物被发现。区分跨物种的致病感染传播与非感染性污染，为疾病生态学和生态系统管理提供了相关信息。
