Heat shock protein gene expression in fish across space and time

温度是影响所有生物的最重要的环境变量之一。自然界中物种的分布模式、生理系统和生化反应速率都受其普遍影响。对温度变化最普遍的分子水平反应之一是一组高度保守的蛋白质的合成，称为热休克蛋白（Hsps）。热休克蛋白通过稳定部分未折叠的蛋白质和防止蛋白质聚集来应对应激诱导的受损蛋白质的增加。热休克蛋白在非应激条件下也作为“分子伴侣”发挥作用，促进蛋白质折叠、运输和细胞信号传导。这种反应的普遍存在，以及热休克蛋白基因序列在完全不同的生物体之间的高度保守，突出了它的重要性，并强调了进一步了解的必要性。恒温（冷血）生物特别容易受到温度变化的影响，因此是研究其环境调节的绝佳模型。在此背景下，我的研究计划结合实地研究和实验室实验，量化热应激如何影响鱼体内热休克蛋白基因的表达和调控。该项目将首次分析鱼类在广泛的纬度分布中热休克蛋白的表达，并将为热休克反应如何参与确定物种范围边界提供有价值的信息。它还将研究热历史对热休克蛋白和生长指标基因表达的影响，为了解与温度变化相关的生理成本提供见解。基因表达的组织特异性和时间变化可能提示温度耐受性的新机制，并揭示这种适应性反应在脊椎动物中的进化。研究细胞膜在温度传感中的作用将增强我们对控制这种适应性反应的机制的认识，并有助于其在自然界中观察到的可塑性。这个项目将促进我们对热应激对鱼类生理影响的理解，增强我们预测、甚至可能减轻未来气候变化的一些生物学后果的能力。

Temperature is one of the most important environmental variables affecting all organisms. Distribution patterns of species in nature, physiological systems, and biochemical reaction rates are all shaped by its pervasive effects. One of the most universal molecular-level responses to temperature change is the synthesis of a highly conserved group of proteins called heat shock proteins (Hsps). Hsps respond to stress-induced increases in damaged proteins by stabilizing partially unfolded proteins and preventing protein aggregation. Hsps also play a role during non-stress conditions as 'molecular chaperones' where they facilitate protein folding, transport and cell signaling. The prevalence of this response, and the high degree of Hsp gene sequence conservation between completely divergent organisms, highlights its importance and emphasizes the need for further understanding. Ectothermic (cold-blooded) organisms are especially vulnerable to temperature change and thus make excellent models in which to examine its environmental regulation. In this context, my research program combines field studies and laboratory experiments to quantify how thermal stress impacts the expression and regulation of Hsp genes in fish. This program will provide the first analysis of Hsp expression across a wide latitudinal distribution of a fish and will contribute valuable information about how the heat shock response participates in determining species range boundaries. It will also examine the impact of thermal history on gene expression of Hsps and growth indicators, providing insight into the physiological costs associated with temperature change. Tissue-specific and temporal changes in gene expression could suggest new mechanisms of temperature tolerance and shed light on the evolution of this adaptive response in vertebrates. Examining the role of the cell membrane in temperature sensing will enhance our knowledge about the mechanisms that control this adaptive response and contribute to its observed plasticity in nature. This program will advance our understanding of the physiological effects of thermal stress on fish and enhance our power to predict, and perhaps even mitigate, some of the biological consequences of future climate change.