The biology and pathogenesis of Deformed Wing Virus, the major virus pathogen of honeybees

蜜蜂主要病毒病原变形翅病毒的生物学和发病机制

• 批准号: BB/M00337X/2
• 负责人: David Evans
• 金额: $ 55.46万
• 依托单位: University of St Andrews
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FM00337X%2F2
• 关键词: biology; pathogenesis; Deformed; Wing; Virus

Honeybees are the most important managed pollinating insects globally. Both honey production and pollination depend upon strong, healthy colonies, a situation that has been threatened over the last century by the global spread of the ectoparasitic mite Varroa destructor. All colonies in the UK (excepting parts of Scotland and some islands) have the mite. Varroa acts as a vector for a range of viruses of honeybees which are transferred when the mite feeds on haemolymph (blood) from the developing pupa. The most important of these viruses is Deformed Wing Virus (DWV). In studies over the last 4 years we have demonstrated that mite infestation preferentially leads to the amplification of a specific virulent form of DWV. In mite-exposed developing pupae this particular virus reaches levels almost 10,000 times higher than seen in the absence of the mite. This is despite the development of an immune response to the infecting virus.We want to understand why the virulent form of DWV observed in mite-infested colonies or mite-exposed pupae replicates to such elevated levels. Is it due to the route by which the virus is acquired - directly into the haemolymph - rather than the usual route which is orally during feeding? Does this route allow the virus to infect tissues or organs it normally does not have access to? Does it allow the virus to bypass the immune response of the honeybee? Does DWV, like many others viruses, carry genes that allow it to suppress the host immune response? Can we 'vaccinate' honeybees before they are exposed to prevent subsequent replication of the virulent virus? Finally we want to understand which host genes, expression of which are suppressed upon DWV infection, contribute to the development of overt disease.Varroa-free honeybee colonies (from Andrew Abrahams, Colonsay) maintained in isolated flight cages or Varroa-infested colonies from our research apiary will be used as a source of individual honeybee larvae which will be harvested and maintained in the laboratory under carefully controlled conditions. We are perhaps the only lab in the UK with expertise in this methodology.Individual larvae will be either fed or injected with a characterised virus population. The tissues and organs in which the virus replicates will be determined using exquisitely sensitive hybridisation techniques on either dissected pupae or sections. We are particularly keen to determine whether virulent forms of the virus cause systemic infections, or whether they preferentially replicate in particular tissues or organs, for example the abdomen and wing buds, both of which exhibit developmental deformities during overt DWV infection.We will repeat these studies in larvae in which we have deliberately suppressed key components of the immune response by inhibiting expression of the genes Dicer and Argonaute. Are these larvae now susceptible to all forms of DWV, not just the virulent variant? We will additionally pre-expose larvae (via feeding; a technique we have acquired from collaborators in Louisiana, USA) to short RNA molecules designed to inhibit DWV replication. Are these larvae protected from infection and disease caused by virulent DWV? We will additionally test whether DWV carries a gene that inhibits the effectiveness of RNA-based immune responses using well-established techniques.The third component of our study is to investigate the role of specific host genes implicated in components of the immune response or development to enhanced susceptibility to DWV-mediated disease. These genes were identified in our recent studies but their importance has yet to be determined. We will suppress individual genes of interest and then challenge larvae with known virus populations.These studies will not only determine why a particular variant of DWV is associated with overt disease in honeybees but will also demonstrate whether it is possible to develop therapies to protect developing honeybees from infection.

蜜蜂是全球最重要的授粉昆虫。蜂蜜的产量和授粉都取决于强大，健康的殖民地，这种情况在上个世纪受到了脑寄生虫螨虫破坏者的全球传播的威胁。英国的所有殖民地（苏格兰和某些岛屿的部分地区除外）都有螨虫。 Varroa充当一系列蜜蜂病毒的载体，当螨虫以来自发育中的pupa的止血（血液）为食时，这些病毒会被转移。这些病毒中最重要的是变形的机翼病毒（DWV）。在过去四年中的研究中，我们证明了螨虫的侵染优先导致特定有毒形式的DWV的扩增。在螨虫暴露的发育pupae中，该特定病毒的水平比没有螨虫的水平高出近10,000倍。尽管发展了对感染病毒的免疫反应的发展。我们想了解为什么在螨虫感染的菌落中观察到的DWV的有毒形式或暴露于螨虫的per鼠重复以这种升高的水平。是由于收到病毒的途径 - 直接进入血淋巴而不是在喂养过程中口服的通常途径？这条路线是否使病毒能够感染通常无法使用的组织或器官？它是否允许病毒绕过蜜蜂的免疫反应？ DWV是否像许多其他病毒一样，携带可以抑制宿主免疫反应的基因？我们可以在暴露于蜜蜂之前“接种”蜜蜂以防止随后复制有毒病毒吗？最后，我们要了解哪些宿主基因，在DWV感染后抑制了哪些宿主基因，有助于公开疾病的发展。无varroa的蜜蜂菌落（来自隔离的飞行笼中的安德鲁·亚伯拉罕（Andrew Abrahams），在我们的研究养蜂场中维持的孤立飞行笼子或varroa侵入的菌落中维持的研究将被仔细地用作单独的蜜蜂的范围，并保存了该措施，并保存了该实验。我们也许是英国唯一具有这种方法专业知识的实验室。个体幼虫将被喂食或注射特征性的病毒群体。使用在解剖的p或切片上使用精确敏感的杂交技术来确定病毒复制的组织和器官。 We are particularly keen to determine whether virulent forms of the virus cause systemic infections, or whether they preferentially replicate in particular tissues or organs, for example the abdomen and wing buds, both of which exhibit developmental deformities during overt DWV infection.We will repeat these studies in larvae in which we have deliberately suppressed key components of the immune response by inhibiting expression of the genes Dicer and Argonaute.这些幼虫现在是否容易受到所有形式的DWV的影响，而不仅仅是强大的变体？我们还将预先膨胀的幼虫（通过喂养；我们从美国路易斯安那州的合作者获得的一种技术）到旨在抑制DWV复制的短RNA分子。这些幼虫是否免受了由毒性DWV引起的感染和疾病？我们还将测试DWV是否具有使用良好的技术抑制基于RNA的免疫反应有效性的基因。我们研究的第三个组成部分是研究与免疫反应或发育中有关的特定宿主基因的作用，以增强对DWV介导的DWV介导的疾病的易感性。这些基因在我们最近的研究中得到了鉴定，但其重要性尚未确定。我们将抑制感兴趣的个体基因，然后挑战已知病毒群体的幼虫。这些研究不仅将确定为什么DWV的特定变体与蜜蜂的明显疾病有关，而且还将证明是否有可能开发保护发展中蜜蜂免受感染的疗法。

项目成果

First come, first served: Superinfection exclusion in Deformed wing virus is dependent upon sequence identity and not the order of virus acquisition

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
• 发表时间: 2021
• 作者: Gusachenko O

Deformed Wing Virus spillover from honey bees to bumble bees: a reverse genetic study

• DOI: 10.1101/2019.12.18.880559
• 发表时间: 2019-01-01
• 期刊: bioRxiv
• 作者: Gusachenko, ON;Woodford, L;Evans, DJ
• 通讯作者: Evans, DJ

First come, first served: superinfection exclusion in Deformed wing virus is dependent upon sequence identity and not the order of virus acquisition.

• DOI: 10.1038/s41396-021-01043-4
• 发表时间: 2021-12
• 期刊: The ISME journal
• 作者: Gusachenko ON;Woodford L;Balbirnie-Cumming K;Evans DJ
• 通讯作者: Evans DJ

Evidence for and against deformed wing virus spillover from honey bees to bumble bees: a reverse genetic analysis.

• DOI: 10.1038/s41598-020-73809-3
• 发表时间: 2020-10-08
• 期刊: Scientific reports
• 影响因子: 4.6
• 作者: Gusachenko ON;Woodford L;Balbirnie-Cumming K;Ryabov EV;Evans DJ
• 通讯作者: Evans DJ

The Iflaviruses Sacbrood virus and Deformed wing virus evoke different transcriptional responses in the honeybee which may facilitate their horizontal or vertical transmission.

• DOI: 10.7717/peerj.1591
• 发表时间: 2016
• 期刊: PeerJ
• 影响因子: 2.7
• 作者: Ryabov EV;Fannon JM;Moore JD;Wood GR;Evans DJ
• 通讯作者: Evans DJ