Ecological and Evolutionary Physiology of the Stress Response and Stress Proteins

生态和进化生理学的一个主要问题是复杂生物体的特征之间的关系，生物体利用不同环境的能力，以及物种在时间上的持久性。拟议的研究部分使用果蝇中的热休克蛋白Hsp 70作为模型性状/生物体/系统来解决这个问题。几乎所有的生物体都表达热休克蛋白（I-Isps），这是一种高度保守的蛋白质，通过分子伴侣的作用来促进胁迫耐受性。由美国国家科学基金会以前的奖项支持的研究已经确定，实验操作果蝇的hsp 7 O基因（编码Hsp 7 O）的拷贝数，足以引起自然热应激的完全生存的变化，并且自然种群在Hsp 70表达方面的变化与其适应性一致。这项拟议的研究将建立在最近的一项重要的初步发现基础上：Hsp 70不仅可以防止热死亡，还可以减轻在成年前阶段暴露于自然热应力的成年人翅膀和翅膀的主要形态异常。这种形态异常可能发生在10%的存活成虫中，并可能损害求偶和交配，领土防御，产卵，飞行和水平衡，每一个都可能是健康的组成部分。这项拟议中的研究将首先将这些异常的发生率与非成年果蝇在实验室中经历的温度联系起来，然后验证自然界中果蝇也存在类似的关系。接下来，拟议的研究将确定这些异常对求偶和交配，领土防御，产卵，飞行和水平衡的影响。最后，所提出的实验将在遗传和实验上操纵Hsp表达，以建立Hsp 7 O在保护或减轻形态缺陷中的作用。拟议研究的预期成果具有整合分子、遗传、功能和进化观点以促进对适应的理解的巨大潜力。

A major issue in ecological and evolutionary physiology is the relationship among the traits of complex organisms, organisms' ability to exploit diverse environments, and species' persistence in time. The proposed investigation in part uses the heat-shock protein Hsp70 in Drosophila as a model trait/organism/system to address this issue. In response to heat or other stresses, nearly all organisms express heat-shock proteins (I-Isps), highly-conserved proteins that contribute to stress tolerance by functioning as molecular chaperones. Research supported by previous NSF awards has established that experimental manipulation of copy number of the hsp7O gene of Drosophila, which encodes Hsp7O, is sufficient to cause changes in outright survival of natural thermal stress, and that natural populations vary in Hsp70 expression in ways that are consistent with it being adaptive. The proposed research will build upon a recent and significant preliminary finding: that not only does Hsp70 protect against heat death, it also mitigates major morphological anomalies in wings and abdomens of adults that have undergone exposure to natural thermal stress during their pre-adult stages. Such morphological abnormalities can occur in 10% of surviving adults and potentially compromise courtship and mating, territorial defense, oviposition, flight, and water balance, each a likely component of fitness. The proposed research will first relate the incidence of these abnormalities to the temperatures that non-adult Drosophila undergo in the laboratory, and then verify that similar relationships occur for Drosophila in nature. Next, the proposed research will establish the effect of these abnormalities on courtship and mating, territorial defense, oviposition, flight, and water balance. Finally, the proposed experiment will genetically and experimentally manipulate Hsp expression to establish the role of Hsp7O in protecting or mitigating morphological defects. The projected outcome of the proposed research has immense potential to integrate molecular, genetic, functional, and evolutionary perspectives to advance understanding of adaptation.