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。但蜜蜂的健康状况在过去十年中一直在下降，自2006-07年以来，加拿大养蜂人每年冬天都会损失超过四分之一的蜂群。在加拿大，冬季蜜蜂的大部分损失归因于已知的原因：寄生螨、真菌感染和天气。蜜蜂有先天的免疫系统，但它对螨虫是无效的，真菌病原体已经找到了一种方法来避免它。因此，养蜂人被迫使用化学品来控制各种传染病，包括上述的螨虫和真菌，但这并不总是有效的，而且无论如何都是不可取的。然而，一些蜜蜂有一个秘密武器，即社会行为，使它们能够击退或至少与会杀死它们的害虫和病原体共存。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。卫生的蜜蜂似乎更有能力感知患病或死亡的同伴，并在疾病传播之前将它们赶出蜂群。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。反过来，这将反馈到我们所参与的平行努力中，可以看到这些发现在现实世界中的应用，用于选择性育种计划，旨在加强加拿大蜜蜂的基因库，使它们能够自然抵抗疾病，而养蜂人不必使用合成化学品。

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.