Mechanistic studies of disease resistance in honey bees

蜜蜂是加拿大农业的重要组成部分，每年至少贡献46亿美元：它们每年生产8万至9万吨蜂蜜，它们的授粉活动直接支持许多水果、坚果和蔬菜作物的生产。但在过去的十年里，蜜蜂的健康状况一直在下降，自2006-07年以来，加拿大养蜂人每年冬天都会失去超过四分之一的蜂群。在加拿大，冬季蜜蜂的大部分损失都归因于已知的原因：寄生虫、真菌感染和天气。蜜蜂有一种天生的免疫系统，但它对螨虫无效，这种真菌病原体已经开发出一种避免这种系统的方法。因此，养蜂人被迫使用化学物质来控制各种传染病，包括上面提到的蠕虫和真菌，但这并不总是有效的，而且无论如何都是不受欢迎的。然而，一些蜜蜂拥有一种秘密武器，这种社会行为使它们能够击退本来会杀死它们的害虫和病原体，或者至少与之共存。其中一种机制被称为卫生行为，我们的团队之前已经确定了这种行为如何发生的潜在解释。看起来，卫生的蜜蜂似乎有更好的装备来感知生病或垂死的巢友，并在疾病传播之前将它们从蜂群中移走。在这里提出的工作中，我们将努力了解在卫生行为中起作用的分子过程。这将反过来反馈到我们正在参与的一项平行努力中，该努力可能会看到这些发现在现实世界中应用于一个选择性育种项目，该项目旨在加强加拿大蜜蜂的基因库，以便它们能够自然抵抗疾病，而不需要养蜂人用合成化学品来治疗它们。

Honey bees are a crucial part of Canadian agriculture, contributing at least $4.6 billion/y: they produce between eighty and ninety thousand tonnes of honey each year and their pollination activities directly support the production of many fruits, nuts and vegetable crops. But the health of honey bees has been declining over the past decade, with Canadian beekeepers losing more than a quarter of their colonies each winter since 2006-07. In Canada, most of the winter losses of bees are attributed to known causes: a parasitic mite, fungal infections and weather. Bees have an innate immune system but it is ineffective against mites and the fungal pathogen has developed a way to avoid it. Thus, beekeepers are forced to use chemicals to control various infectious diseases, including the mite and fungi mentioned, but this is not always effective and is in any case undesirable. Some bees have a secret weapon though, social behaviours that enable them to fight off, or at least live with, pests and pathogens that would otherwise kill them. One of these mechanisms is called hygienic behaviour and our group has previously identified a potential explanation for how this behaviour can happen. It appears as if hygienic bees are better equipped to sense diseased or dying nest-mates and remove them from the colony before the disease spreads. In the work proposed here we will work to understand the molecular processes at work in hygienic behaviour. This will, in turn, feed back into a parallel effort we are involved in that could see the real-world application of these findings into a selective breeding program that aims to strengthen the gene pool of Canadian bees so that they can naturally resist disease without beekeepers having to treat them with synthetic chemicals.