Ecological and Evolutionary Physiology of the Stress Response and Stress Proteins

小行星9408216 几乎所有的生物体都能合成一些特有的蛋白质来应对高温和其他胁迫，这些蛋白质被称为“胁迫蛋白”或“热休克蛋白”。在实验室中，对压力的抵抗力的提高与这些蛋白质的合成相一致。目前，科学知识的主要空白包括：（1）在实验室中诱导这些蛋白质的条件是否在自然界中遇到过;（2）这些蛋白质在自然条件下是否具有适应性;（3）这些蛋白质实际上如何提高对压力的抵抗力。该项目将通过检查果蝇（果蝇）的品系来填补这些空白，这些果蝇经过基因工程改造，可以合成不同水平的关键应激蛋白hsp 70。该项目首先将记录野生果蝇自然暴露于两种可能的压力（温度和乙醇），并测量这些生物体中相应的hsp 70浓度。接下来，它将使用这些信息来设计实验室实验，在这些实验中，hsp 70表达不同的果蝇品系暴露于每种应激。在首次确认hsp 70的预期差异实际上发生在实验条件下后，该项目将评估差异hsp 70表达对果蝇在压力下成功生长和繁殖能力的影响。 最后，该项目将用发光蛋白改造hsp 70表达不同的果蝇细胞系，以测试hsp 70是否可以修复应激损伤蛋白。拟议的研究意义重大，因为（1）它将收集现代生物学研究的主要模型之一果蝇所经历的自然条件的基本但目前尚无法获得的数据;（2）它将评估分子/细胞水平上的应激反应表现与生物体表现之间的联系;（3）它将前瞻性地确定细胞/分子水平研究的候选机制;（4）它将为先验预测和测试生理特征的进化奠定基础。 ***

9408216 Feder Almost all organisms synthesize a number of characteristic proteins in response to high temperatures and other stresses; these are termed "stress proteins" or "heat-shock protein". In the laboratory, improved resistance to stress coincides with the synthesis of these proteins. At present, major gaps in scientific knowledge include: (1) Whether the conditions that induce these proteins in the laboratory are ever encountered in nature; (2) Whether the proteins are adaptive under natural conditions; (3) How these proteins actually improve resistance to stress. This project will contribute to the filling of these gaps by examining strains of fruit flies (Drosophila) that have been genetically engineered to synthesize very different levels of a key stress protein, hsp70. The project first will document natural exposure of wild Drosophila to two likely stresses (temperature and ethanol), and measure corresponding hsp70 concentrations in these organisms. Next, it will use this information to design laboratory experiments in which Drosophila strains differing in hsp70 expression undergo exposure to each stress. After first confirming that the expected differences in hsp70 actually occur under experimental conditions, the project will assess the consequences of differential hsp70 expression for the ability of Drosophila to grow and reproduce successfully under stress. Finally, the project will engineer Drosophila cell lines differing in hsp70 expression with a light-emitting protein to test whether hsp70 can repair a stress-damaged protein. The proposed research is significant because (1) it will gather basic but presently unavailable data on the natural conditions experienced by Drosophila, one of the primary models in modern biological research; (2) it will assess the linkages, if any between manifestations of the stress response at the molecular/cellular level and organismal performance; (3) it will prospectively identify candidate mechanisms for study at the cellular/molecular level; and (4) it will lay the groundwork for a priori predictions and test of the evolution of physiological characteristics. ***