First come, first served: Superinfection exclusion in Deformed wing virus is dependent upon sequence identity and not the order of virus acquisition
First come, first served: Superinfection exclusion in Deformed wing virus is dependent upon sequence identity and not the order of virus acquisition
复制标题
先到先得：变形翼病毒的重复感染排除取决于序列同一性，而不是病毒获取的顺序
DOI：
10.1101/2021.03.22.436467
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Gusachenko O
中科院分区：
文献类型：
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作者：
Gusachenko O
变形翼病毒（DWV）是全球分布最重要的蜜蜂病原体，当由外寄生破坏蜂携带时，与高水平的蜂群损失有关。不同的DWV类型可能在致病性上有所不同，并且据报道，在顺序感染时表现出重复感染排除，这在阿瓦罗亚感染的群体中是不可避免的。我们使用反向遗传方法来研究遗传上不同或相关的病毒株之间的竞争和相互作用，分析病毒载量随时间的变化，报告基因表达病毒的组织分布以及病毒变体之间的重组。不管病毒获得的顺序如何，短暂的竞争都发生了，表明没有方向性或优势。在较长时期内，与预先存在的感染竞争的能力与疫苗的遗传分化有关。在整个DWV基因组中观察到遗传重组，通过深度测序确定重组占种群的约2%。我们认为，如果发生重复感染排斥，是对相关病毒的交叉反应性RNAi反应的结果，这解释了一种病毒类型对另一种病毒缺乏优势。更好地了解双重感染和重复感染的后果将为开发交叉保护的蜜蜂疫苗和大规模DWV传播和进化提供信息。
Deformed wing virus (DWV) is the most important globally distributed pathogen of honey bees and, when vectored by the ectoparasiteVarroa destructor, is associated with high levels of colony losses. Divergent DWV types may differ in their pathogenicity and are reported to exhibit superinfection exclusion upon sequential infections, an inevitability in aVarroa-infested colony. We used a reverse genetic approach to investigate competition and interactions between genetically distinct or related virus strains, analysing viral load over time, tissue distribution with reporter gene-expressing viruses and recombination between virus variants. Transient competition occurred irrespective of the order of virus acquisition, indicating no directionality or dominance. Over longer periods, the ability to compete with a pre-existing infection correlated with the genetic divergence of the inoculae. Genetic recombination was observed throughout the DWV genome with recombinants accounting for ~2% of the population as determined by deep sequencing. We propose that superinfection exclusion, if it occurs at all, is a consequence of a cross-reactive RNAi response to the viruses involved, explaining the lack of dominance of one virus type over another. A better understanding of the consequences of dual- and superinfection will inform development of cross-protective honey bee vaccines and landscape-scale DWV transmission and evolution.