Physiological and Behavioural Regulation of Animal Stress Responses

动物对压力的反应是采取策略来应对动态平衡的破坏。如果压力持续或严重，这些压力应对机制可能不充分，动物对疾病和/或死亡的易感性增加。我的研究计划的长期目标是了解动物的行为、生理和细胞应激反应策略之间的反馈。我的动机有两个：1)了解水生动物如何应对不断变化的、往往充满压力的环境；2)利用鱼类及其细胞作为模型，了解基本的压力应对策略。在短期内，我们将讨论动物的生理(对象1)和行为(对象2)状态如何影响其对应激的反应和耐受性。我提议进行与生态相关的全动物实验和机械细胞实验，以解决两个短期目标。第一项研究利用渗透压和热应激来研究棘鱼和八头鳗之间的化学和分子伴侣之间的关系。细胞使用这些伴侣来减轻压力引起的细胞损伤，并帮助适当的蛋白质折叠。分子伴侣直接与蛋白质结合并协助折叠，热休克蛋白(HSPs)就是其中一个被广泛研究的例子。另一方面，化学伴侣，如渗透分子，三甲胺氧化物(TMAO)，则间接与蛋白质相互作用，抑制蛋白质聚集。这里最重要的假设是，化学伴侣浓度较高的动物分子伴侣浓度较低。我们的发现可能揭示伴侣在应激过程中的新角色，并为这两个伴侣系统如何在细胞中根本整合提供洞察。我的第二个目标将解决社会压力如何影响对热应激的反应。在这里，我们将使用红树林溪流鱼，唯一已知的自交两性脊椎动物，来分离遗传和梳理环境变化对行为和生理表型的贡献。有了这个独特的模型，我们将确定热生理和同种基因谱系之间的耐受性，并研究以攻击形式的社会行为如何影响动物对环境变化的反应。我们还将确定社会相互作用和热应激反应的分子特征，因为我们预测这些表型可能受到共同机制的调节。使用基因作为一个自变量来检测行为和热生理的可变性，将有助于理清遗传和环境对抗逆性生理的影响。总体而言，这项研究将提供对压力耐受性的生理基础的更多了解，使我们能够对环境变化对水生动物的影响做出明智的预测。

Animals respond to stress by engaging in strategies to cope with the disruption in homeostasis. If the stress is prolonged or severe, these stress-coping mechanisms may be insufficient and the animal has increased susceptibility to disease and/or death. The long-term goal of my research program is focused on understanding feedback amongst behavioural, physiological and cellular stress response strategies in animals. My motivation is twofold: 1) to understand how aquatic animals are dealing with a changing, often stressful environment and 2) to use fish and their cells as models to understand fundamental stress-coping strategies. In the short term, we will address how the physiological (Obj 1) and behavioural (Obj 2) state of the animal influences its response and tolerance to stress. I am proposing ecologically relevant whole-animal experiments and mechanistic cell-based experiments to address two short-term objectives. The first uses osmotic and heat stress in elasmobranchs and hagfishes to investigate the relationship between chemical and molecular chaperones. Cells use these chaperones to mitigate stress-induced cellular damage and assist with proper protein folding. The molecular chaperones, of which the heat shock proteins (HSPs) are a well-studied example, bind directly to proteins and assist with folding. Chemical chaperones, such as the osmolyte, trimethylamine oxide (TMAO), on the other hand, interact indirectly with proteins to inhibit protein aggregation. The overarching hypothesis here is that animals with high concentrations of chemical chaperones will have lower concentrations of molecular chaperones. Our findings could reveal novel roles for chaperones during stress and provide insight into how the two chaperones systems are fundamentally integrated in cells. My second objective will address how social stress affects responses to thermal stress. Here, we will use the mangrove rivulus fish, the only known selfing hermaphroditic vertebrate, to isolate genetics and tease apart the contributions of environmental variation on behavioural and physiological phenotypes. With this unique model, we will determine thermal physiology and tolerance between and within isogenic lineages and investigate how social behaviour, in the form of aggression, affects an animal’s response to environmental change. We will also determine the molecular signatures of social interactions and the thermal stress response as we predict that these phenotypes may be regulated by common mechanisms. The ability to use genotype as an independent variable to examine variability in behaviour and thermal physiology will help to disentangle genetic and environmental effects on the physiology of stress resistance. Overall, this research will provide a greater understanding of the physiological underpinnings of stress tolerance allowing us to make informed predictions on the impact of environmental change on aquatic animals.