Transcriptomic diagnostics for identifying interactive effects of pesticides, food deficiency, and heat stress on bee health.

蜜蜂授粉对许多野生植物的生存和许多作物的收获至关重要。然而，近几十年来，全世界的蜜蜂数量一直在减少。这就产生了巨大的风险和潜在的巨大成本——仅在英国，每年授粉的经济价值就估计为4.3亿英镑。最近蜜蜂数量下降的原因包括栖息地丧失，减少了获取食物的机会，温度变化，以及接触杀虫剂。事实上，之前批准使用的杀虫剂对蜜蜂产生了意想不到的影响，降低了它们觅食的能力，最终影响了它们的生存。因此，三种最常用的农药于2013年暂停使用，并于2018年被欧盟委员会禁止使用。这是否意味着仍然被授权的农药对蜜蜂是安全的？不幸的是，评估农药影响的方法过于粗糙，无法确定。为了获得清晰度，我们将应用一种分子医学方法，这种方法在过去十年中极大地改善了对人类疾病的治疗和理解。我们将运用这项新技术来了解一种已被确定的新烟碱类杀虫剂（醋氨虫）的效果，以及两种被宣布为“对蜜蜂安全”的新杀虫剂（有一些争议）：亚砜和氟吡喃酮。为此，我们将进行对照实验，在实验中，我们将蜜蜂暴露在单独的农药和农药组合中——就像邻近的农场使用不同的产品一样。此外，我们将进行实验，以确定在模拟更温暖的气候时，农药的影响是否会发生变化，或者食物的营养质量是否较低——这在以单一栽培为主的景观中很常见。我们的实验对象是两种常见的英国蜜蜂，它们也被广泛培育用于农业授粉：群居的大黄蜂Bombus terrestris和独居的红石匠蜜蜂Osmia bicornis。我们应用于蜜蜂的“转录组诊断”将为每个实验提供数万个测量值，而不是通过传统方法获得的少数测量值。事实上，我们将测量蜜蜂大脑、飞行肌肉和解毒组织中的12000个基因组成块中每一个基因活动水平的变化。这种方法非常灵敏，能够直接检测到蜜蜂生理和新陈代谢的细微变化。此外，由于我们将测量解毒组织以及大脑和肌肉中的基因活动，我们将能够确定活动水平的变化是否有助于蜜蜂应对农药暴露。我们的工作将1)提供迫切需要的关于这些特定杀虫剂对蜜蜂的影响的见解；2)可能揭示授权农药以前未知的影响；3)识别这些被认为作用方式相似的农药之间的潜在差异；4)澄清农药之间或与其他环境压力源之间是否存在“非加性”相互作用；5)一种物种的毒性结论是否具有另一种物种的代表性；6)明确地证明了应用“转录组诊断”方法来确定蜜蜂健康的能力和灵敏度。我们通过该项目获得的生物学知识将为目前批准的农药的监管决策提供信息。此外，我们期望我们开发的方法将从根本上改善未来农药研究和监管的评估。最终，两者都将改善英国蜜蜂的命运。

Pollination by bees is essential for the survival of many wild plants and harvesting of many crops. Over recent decades, however, bees have been in decline worldwide. This creates a major risk and potentially a huge cost - the economic value of pollination is estimated to be £430 million per year in the UK alone. Causes for the recent bee declines include habitat loss which reduces access to food, changing temperatures, and exposure to pesticides. Indeed, previously authorised pesticides in fact have unintended impacts on bees, reducing their abilities to forage for food, and ultimately their survival. Three of the most commonly used pesticides were thus suspended in 2013 and banned by the European Commission in 2018.Does this mean that pesticides that remain authorised pesticides are safe for bees? Unfortunately, the manners by which the effects of pesticides are evaluated have been too crude to be certain. To obtain clarity, we will apply a type of molecular medicine approach that has over the past decade dramatically improved treatment and understanding of human diseases. We will apply the new technology to understand the effects of one established neonicotinoid pesticide (acetamiprid), and two new pesticides that have (with some contention) been heralded as "bee-safe" alternatives to the banned neonicotinoids: sulfoxaflor and flupyradifurone. For this purpose, we will perform controlled experiments in which we expose bees to individual pesticides and pesticide combinations - as occurs when neighbouring farms apply different products. Furthermore, we will perform experiments to determine whether the effects of pesticides change when simulating a warmer climate or if food has low nutritional quality - as is common in landscapes dominated by monocultures. Our experiments will be on two common British bee species that are also extensively bred for agricultural pollination: the social large earth bumblebee Bombus terrestris and the solitary red mason bee Osmia bicornis. The "transcriptomic diagnostics" we apply to the bees will provide tens of thousands of measurements per experiment - rather than the handful obtained through traditional approaches. Indeed, we will measure changes in activity levels for each of the 12,000 gene building blocks in brain, flight muscle and a detoxification tissue of bees. This approach is highly sensitive and able to directly detect even subtle changes in the bees' physiologies and metabolisms. Furthermore, because we will measure gene activity in a detoxification tissue as well as brain and muscle, we will be able to determine whether changes in activity level are helping the bees cope with pesticide exposure. Our work will 1) provide urgently needed insight into the effects of these specific pesticides on bees; 2) likely reveal previously unknown effects of authorised pesticides; 3) identify potential differences between these pesticides which are thought to act in similar manners; 4) clarify whether there are "non-additive" interactions between pesticides or with other environmental stressors; 5) whether conclusions about toxicity for one species are representative of another; and 6) unambiguously demonstrate the power and sensitivity of applying the "transcriptomic diagnostics" approach for determining bee health.The biological knowledge we gain through this project will inform regulatory decisions about the currently authorised pesticides. Furthermore, we expect that the approach we develop will fundamentally improve future evaluation of pesticides for research and regulation. Ultimately, both will improve the fates of Britain's bees.