Identifying the link between viral infections and foraging behaviour in the honeybee brain

昆虫传粉者对全球粮食生产和粮食安全至关重要，蜜蜂是粮食生产系统中最重要的受控传粉物种。在过去的几十年里，蜜蜂一直受到全球健康危机的影响。造成这场危机的原因是多方面的，包括现代农业做法、生境变化、气候变化、农药和病原体。在英国，重要的病原体是最近引入的瓦螨和长期存在的地方性畸形翅病毒（DWV）。瓦螨属和DWV一起成为一种致命的鸡尾酒，严重影响越冬损失。DWV对个体蜜蜂的一个更微妙的影响，但对殖民地本身的关键影响是DWV对觅食活动的负面影响。感染DWV的蜜蜂寿命缩短，并通过加速行为成熟过早开始觅食。受感染的蜜蜂飞行的距离和持续时间较短，但进行更多的觅食旅行，即它们过度活跃。在早期的研究中，DWV被证明会损害学习和记忆的形成-这是摇摆舞中传递的信息之后觅食行为的关键步骤。在这个项目中，你将研究病毒存在于蜜蜂大脑中的影响。您将采用一系列不同的技术来从多个角度解决问题。首先，您将通过PER和摇摆舞的定量分析来执行反向学习试验，以选择具有不同认知能力的蜜蜂。此后，您将通过实时PCR定量蜜蜂大脑中的DWV负载。将选择病毒载量与认知表现之间存在最强相关性的样本进行转录组学方法，其中将量化全脑基因集的表达以鉴定受DWV存在影响的关键基因。学生奖学金的最后一部分将致力于将两种创新技术应用于这一研究领域。在第一种方法中，您将使用功能显微镜来识别病毒颗粒在不同大脑区域中的确切位置。病毒颗粒浓度最高的区域将进行单细胞RNA测序，以表征病毒感染在单个神经元水平上的影响。在第二种方法中，将对蜜蜂进行抗病毒治疗，以测试是否可以通过降低大脑中的病毒水平来拯救大脑基因表达，从而恢复认知功能。

Insect pollinators are incredibly important to global food production and food security, with honey bees being by far the most important managed pollinating species in food production systems. Over the past few decades honey bees have been affected by a health crisis worldwide. The cause this crisis is multifactorial and includes modern agricultural practices, habitat changes, climate changes, pesticides and pathogens. Here in the UK, among the important pathogens are the recently introduced Varroa mite and the long-standing and endemic deformed wing virus (DWV). Together, Varroa and DWV have become a lethal cocktail severely affecting overwintering losses.One of the more subtle effects of DWV on individual bees, but a critical effect on the colony itself, is DWV's negative effect on foraging activity. DWV-infected bees have a reduced life span and start foraging prematurely through accelerated behavioural maturation. Infected bees fly shorter distance and duration but perform more foraging trips, i.e. they are hyperactive. In earlier studies, DWV was demonstrated to impair learning and memory formation - a critical step for foraging behaviour following on from communication delivered in the waggle dance.In this project you will investigate the implications of the virus presence in the bee brain. You will employ a range of different techniques to approach the problem from multiple angles. First, you will perform reversal learning assays through PER and quantitative analysis of the waggle dance to select bee with different cognitive abilities. Thereafter you will quantify DWV loads in the bee brain by means of real-time PCR. Samples that present the strongest correlation between viral loads and cognitive performance will be selected for a transcriptomic approach where the expression of the whole brain gene set will be quantified to identify key genes affected by the presence of DWV. The last part of the studentship will be dedicated to applying two innovative techniques to this area of research. In the first approach you will use functional microscopy to identify the exact location of viral particles in different brain regions. Areas with the highest concentration of viral particles will be subjected to single-cell RNA sequencing, to characterize the effects the viral infection at the level of individual neurons. In the second approach antiviral therapies will be administered to bees to test whether brain gene expression can be rescued by reducing viral levels in the brain and, as a consequence, also cognitive functions can be restored..