Contaminant effects on chemical communication in aquatic animals: targeted effects and recovery during continuous exposure conditions

我的研究的长期目标是了解污染物引起的水生动物之间的化学通讯系统的损害的原因和后果。这些动物利用气味来避免捕食，寻找食物或繁殖。信息分子以氨基酸（食物和迁移线索）、信息素（性线索）或胆汁酸（捕食者线索）的形式被嗅觉系统感知，并触发刻板的行为反应。环境污染会干扰嗅觉，导致适应不良的状况：信息中断。“污染物引起的信息破坏已知会影响许多在实验室和现场条件下暴露于环境相关污染物浓度的物种。嗅觉感觉神经元（OSNs）的三个亚群发生在鱼类：纤毛，微绒毛和隐窝细胞，分别是敏感的胆汁酸，氨基酸，或信息素。不同的OSN亚型使用不同的分子机制，使我们能够区分哪种OSN亚型负责处理特定的气味。我们已经确定金属靶向影响特定行为的OSN亚型。在野生种群中，鱼对特定气味的敏感性可能会受到生态环境的影响。例如，当食物稀缺时，由于微绒毛OSN增加，鱼类可能对食物线索过敏。相反，在被针对纤毛OSN的物质污染的环境中，鱼类可能无法检测和避免捕食者。本研究的目标是：（一）确定特定OSN亚型功能障碍与鱼类行为影响之间的关系，（二）确定生态环境或生理状态是否可以补偿污染物对嗅觉的影响，（三）确定鱼类或无脊椎动物在持续接触期间是否会恢复，如果是，以确定恢复的机制（iv）以确定自然种群是否适应或补偿污染物诱导的化学感觉缺陷。实验方法是在受控和现场条件下研究实验室饲养的和野生的鱼类和水生无脊椎动物。将使用成熟的行为和神经生理学技术（即，嗅觉电描记术; EOG）。药理学试剂将用于确定OSN参与特定线索的检测。这项工作的意义在于了解化学通讯系统在水生生态系统中的重要作用，以及对水生动物种群的相关风险，即使是非常低浓度的金属污染的环境。由于化学通讯系统介导与生存、生长和繁殖相关的行为，信息中断可能导致适应不良的影响，对整个生态系统产生重要影响。

The long-term objective of my research is to understand the causes and consequences of contaminant-induced impairment of chemical communication systems among aquatic animals. These animals use smells to avoid predation, find food, or reproduce. Infomolecules, in the form of amino acids (food and migratory cues), pheromones (sex cues), or bile acids (predator cues), are perceived by the olfactory system and trigger stereotypical behavioural responses. Environmental contamination can interfere with olfaction leading to a maladaptive condition: 'infodisruption.' Contaminant-induced infodisruption is known to affect many species exposed to environmentally-relevant contaminant concentrations under lab and field conditions. Three subpopulations of olfactory sensory neurons (OSNs) occur in fish: ciliated, microvillous, and crypt cells that are sensitive to bile acids, amino acids, or pheromones, respectively. Different molecular mechanisms are used by different OSN-subtypes, allowing us to differentiate which OSN-subtype is responsible for processing specific odours. We have established that metals target OSN subtypes which affect specific behaviours. In wild populations, a fish's sensitivity to a particular smell may be affected by ecological context. For example, fish may be hypersensitive to food cues when food is scarce because of increased microvillous OSNs. Conversely, fish in environments contaminated by substances that target ciliated OSNs may not be able to detect and avoid predators. The objectives of this research are: (i) To establish the relationship between specific OSN-subtype dysfunction and behavioural effects in fish, (ii) to determine if ecological context or physiological state can compensate for contaminant effects on olfaction, (iii) to determine if recovery in fish or invertebrates occurs during continuous exposure, and if so, to determine the mechanism of recovery (iv) to determine if natural populations adapt or compensate for contaminant-induced chemosensory deficits. The experimental approach is to study both lab-reared and wild fish and aquatic invertebrates under controlled and field conditions. Chemosensory function will be measured using well-established behavioural and neurophysiological techniques (i.e., electro-olfactography; EOG). Pharmacological agents will be used to determine OSN involvement in the detection of specific cues. The significance of this work lies in understanding the vital role of chemical communication systems in aquatic ecosystems, and the associated risk to aquatic animal populations inhabiting environments contaminated with even very low concentrations of metals. Because chemical communication systems mediate behaviours associated with survival, growth, and reproduction, info-disruption can lead to maladaptive effects that can have important ramifications to the entire ecosystem.