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非常重要，蜜蜂是迄今为止粮食生产系统中最重要的受控授粉物种。在过去的几十年里，蜜蜂受到了全球健康危机的影响。这场危机的原因是多方面的，包括现代农业做法、栖息地变化、气候变化、杀虫剂和病原体。在英国，重要的病原体包括最近引入的瓦罗螨和长期存在的地方性变形翅病毒(DWV)。Varroa和DWV一起成为致命的鸡尾酒，严重影响越冬损失。DWV对单个蜜蜂的更微妙的影响之一，但对蜂群本身的关键影响是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开始过早觅食。受感染的蜜蜂飞行的距离和持续时间较短，但觅食的次数更多，即它们非常活跃。在早期的研究中，DWV被证明会损害学习和记忆的形成--这是在摇摆舞中传递信息后觅食行为的关键步骤。在这个项目中，你将研究病毒在蜜蜂大脑中存在的含义。您将使用一系列不同的技术从多个角度处理问题。首先，你将通过对摇摆舞的PER和量化分析来进行反向学习分析，以选择具有不同认知能力的蜜蜂。此后，您将通过实时聚合酶链式反应来量化蜜蜂大脑中的DWV负载。病毒载量和认知表现之间相关性最强的样本将被选择用于转录转录方法，其中整个大脑基因集的表达将被量化，以确定受DWV存在影响的关键基因。学生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，你将使用功能显微镜来确定病毒颗粒在不同大脑区域的确切位置。病毒颗粒密度最高的区域将接受单细胞RNA测序，以在单个神经元水平上表征病毒感染的影响。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挽救大脑基因的表达，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..