THE INFLUENCE OF PREVIOUS EXPOSURE TO A MIXTURE OF HEAVY METALS ON TOLERANCE

先前接触重金属混合物对耐受性的影响

• 批准号: 6296587
• 负责人: WILLIAM H CLEMENTS
• 金额: $ 14.74万
• 依托单位: COLORADO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2001-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6296587
• 关键词: Arthropoda; acidity /alkalinity; alternatives to animals in research; cadmium; copper; environmental toxicology; heavy metals; lead; pollutant interaction; polymerase chain reaction; single strand conformation polymorphism; temperature; water environment; water pollution; water quality; zinc

This research will examine the influence of previous exposure to a mixture of heavy metals (Cd, Cu, Pb, Zn) on population and community responses to subsequent stress. We will evaluate mechanisms responsible for enhanced tolerance by relating responses at the molecular and population level to change observed at higher levels of organization. Studies will be conducted using benthic macroinvertebrate populations and communities collected from the Arkansas River, a U.S. EPA Superfund site that has been polluted by metals for over 100 years. At the population level, we hypothesize that tolerance of macroinvertebrates to metals results from increased production of metal-binding proteins. Studies conducted in collaboration with Dr. Barry Beaty (Project 5) will investigate molecular changes associated with increased production of metal-binding proteins. We hypothesize that increased tolerance at the population level will have cascading effects on higher levels of organization. At the community level. We will assess the relative importance of both intraspecific (physiological and/or genetic changes) and interspecific (replacement of sensitive species by tolerant species) tolerance mechanisms. Finally, this research will investigate the effects of novel stressors (e.g., increased temperature, acidification) on previously-exposed and naive systems. Because increased tolerance to metals may be associated with decreased genetic heterogeneity and increased metabolic costs, we hypothesize that systems previously-exposed to metals will be more susceptible to novel stressors.

这项研究将检查以前暴露于混合物的影响 重金属（CD，CU，PB，ZN）的人口和社区回应 随后的压力。 我们将评估负责增强的机制 通过将分子和人口水平的反应与 在较高的组织中观察到的变化。 研究将是 使用底栖大型无脊椎动物种群和社区进行 从阿肯色河（Arkansas River）收集，这是美国EPA超级基金网站 被金属污染了100多年。 在人口一级，我们 假设大型无脊椎动物对金属的耐受性来自 金属结合蛋白的产生增加。 进行的研究 与Barry Beaty博士（项目5）的合作将研究分子 与金属结合蛋白的产生增加有关的变化。 我们 假设在人口一级的容忍度提高将具有 级联对更高级别的组织的影响。 在社区 等级。 我们将评估两种种内的相对重要性 （生理和/或遗传变化）和种间（替代 耐受物种的敏感物种）耐受机制。 最后，这个 研究将研究新型压力源的影响（例如，增加 温度，酸化）先前暴露和幼稚的系统。 因为对金属的耐受性增加可能与降低有关 我们假设遗传异质性和增加代谢成本，我们假设 以前暴露于金属的系统将更容易受到新颖的影响 压力源。