Direct Evidence for Infection of Varroa destructor Mites with the Bee-Pathogenic Deformed Wing Virus Variant B, but Not Variant A, via Fluorescence In Situ Hybridization Analysis
Direct Evidence for Infection of Varroa destructor Mites with the Bee-Pathogenic Deformed Wing Virus Variant B, but Not Variant A, via Fluorescence In Situ Hybridization Analysis
复制标题
DOI：
10.1128/jvi.01786-20
复制
发表时间：
2021-03-01
影响因子：
5.4
通讯作者：
Genersch, Elke
中科院分区：
文献类型：
--
作者：
Gisder, Sebastian;Genersch, Elke
变形翅病毒（DWV）是一种蜜蜂致病性的单链和正链RNA病毒，在世界范围内引起了严重的蜂群损失。DWV在蜜蜂之间水平或垂直传播时，主要引起隐蔽感染，而不伴有任何可见症状或损害。DWV通过外寄生螨狄斯瓦螨（Varroa destructor）向发育中的蜜蜂蛹传播后，发生明显感染。明显感染的症状是蛹死亡，蜜蜂出现翅膀变形和缩短的触角，或由于大脑感染造成的认知障碍。到目前为止，已经描述了DWV的三种变体，DWV-A、DWV-B和DWV-C。虽然人们普遍认为，V. destructor作为DWV的载体，但关于螨是否仅作为机械载体或DWV是否可以感染螨，从而将其用作生物载体的问题一直存在激烈争论，因为在文献中可以找到支持这两种假设的数据。为了解决这一科学争议，我们分析了puppelicDWV感染螨与螨荧光原位杂交新建立的协议，并证明了DWV特异性信号螨细胞内。我们提供了令人信服的和直接的证据，DWV-B感染肠上皮细胞和唾液腺的破坏弧菌。相比之下，没有证据表明DWV-A感染螨细胞被发现。我们的数据是关键，以了解DWV的病理生物学，螨的作用，作为一种生物DWV载体，和准种动态的这种RNA病毒之间切换昆虫和蛛形纲动物的宿主species.IMPORTANCE变形翼病毒（DWV）是一种蜜蜂致病，原本相当良性，单链和正链RNA病毒。只有这种病毒通过外寄生螨狄斯瓦螨传播给蜜蜂，才会导致个体的致命或症状性感染，通常随后整个蜂群崩溃。关于螨是否仅作为机械病毒载体或DWV是否可以感染螨并因此将其用作生物载体的研究导致了不同的结果。在我们使用荧光原位杂交的研究中，我们提供了令人信服的和直接的证据，至少DWV-B变异感染肠道上皮和唾液腺的破坏弧菌。因此，DWV的宿主范围包括蜜蜂（昆虫纲）和螨（蛛形纲）。我们的数据有助于更好地了解蜜蜂，V. destructor和DWV之间的三角关系，以及这种病毒性蜜蜂病原体的毒力演变。
Deformed wing virus (DWV) is a bee-pathogenic, single- and positive-stranded RNA virus that has been involved in severe honey bee colony losses worldwide. DWV, when transmitted horizontally or vertically from bee to bee, causes mainly covert infections not associated with any visible symptoms or damage. Overt infections occur after vectorial transmission of DWV to the developing bee pupae through the ectoparasitic mite Varroa destructor. Symptoms of overt infections are pupal death, bees emerging with deformed wings and shortened abdomens, or cognitive impairment due to brain infection. So far, three variants of DWV, DWV-A, DWV-B, and DWV-C, have been described. While it is widely accepted that V. destructor acts as vector of DWV, the question of whether the mite only functions as a mechanical vector or whether DWV can infect the mite, thus using it as a biological vector, is hotly debated because in the literature data can be found that support both hypotheses. In order to settle this scientific dispute, we analyzed putatively DWV-infected mites with a newly established protocol for fluorescence in situ hybridization of mites and demonstrated DWV-specific signals inside mite cells. We provide compelling and direct evidence that DWV-B infects the intestinal epithelium and the salivary glands of V. destructor. In contrast, no evidence for DWV-A infecting mite cells was found. Our data are key to understanding the pathobiology of DWV, the mite's role as a biological DWV vector, and the quasispecies dynamics of this RNA virus when switching between insect and arachnid host species.IMPORTANCE Deformed wing virus (DWV) is a bee-pathogenic, originally rather benign, single- and positive-stranded RNA virus. Only the vectorial transmission of this virus to honey bees by the ectoparasitic mite Varroa destructor leads to fatal or symptomatic infections of individuals, usually followed by collapse of the entire colony. Studies on whether the mite only acts as a mechanical virus vector or whether DWV can infect the mite and thus use it as a biological vector have led to disparate results. In our study using fluorescence in situ hybridization, we provide compelling and direct evidence that at least the DWV-B variant infects the gut epithelium and the salivary glands of V. destructor. Hence, the host range of DWV includes both bees (Insecta) and mites (Arachnida). Our data contribute to a better understanding of the triangular relationship between honey bees, V. destructor, and DWV and the evolution of virulence in this viral bee pathogen.