Functional Studies of Cytosolic Antioxidant Proteins

描述(由申请人提供)：研究的总体目标 这里提出的是破译氧化还原平衡、氧化 真核细胞中的应激、金属离子代谢及其在人类中的作用 疾病和衰老。特别是，超氧应激的详细性质， 即由直接化学物质引起的氧化应激的成分 超氧化物在活细胞内的反应，将被寻找。校长 模型系统是发芽酵母酿酒酵母，但假设 从酵母研究中提取的物质也将在小鼠身上进行测试。校长 待研究的蛋白质是铜锌超氧化物歧化酶(CuZnSOD)，它是 一种抗氧化酶及其铜伴侣(CCS)，据信 通过插入铜来激活CuZnSOD。第一个主要目标是澄清 铁在过氧化应激中的作用。我们将通过研究大自然来接近它。 在缺乏铜锌超氧化物歧化酶的生物体中积累的游离铁， 超氧化物使某些含铁蛋白质失活，以及 基因抑制物降低超氧化物歧化敏感性的机制 缺乏铜锌超氧化物歧化酶的酵母菌株。第二个主要目标是发现 铜锌代谢、超氧化物歧化应激与机体的关系(S) 铜锌超氧化物歧化酶的金属化态。研究的目的将是了解 CCS在CuZnSOD中插入铜的机理及其定态 铜锌超氧化物歧化酶在不同组织中的金属化。了解金属化是如何 铜锌超氧化物歧化酶的研究已经完成，它在不同组织中的调控方式将有助于 我们更好地了解人类的抗氧化剂防御，从而了解某些疾病 各州。总体而言，这项工作将促进我们对细节的理解 过氧化应激的化学机制、铁、铜和锌的作用 在过氧化应激的表现中，并最终发挥作用 过氧化应激与人体健康和衰老

DESCRIPTION (provided by applicant): The overall objective of the research proposed here is to decipher the relationships between redox balance, oxidative stress, and metal ion metabolism in eukaryotic cells and their roles in human disease and aging. In particular, the detailed nature of superoxide stress, i.e., that component of oxidative stress which is due to direct chemical reactions of superoxide within living cells, will be sought. The principal model system is the budding yeast Saccharomyces cerevisiae, but hypotheses derived from the yeast studies will be tested in mice as well. The principal proteins to be studied are copper-zinc superoxide dismutase (CuZnSOD), which is an antioxidant enzyme, and its copper chaperone (CCS), which is believed to activate CuZnSOD by inserting copper. The first major goal is to clarify the role of iron in superoxide stress. It will be approached by studying the nature of the free iron that accumulates in organisms lacking CuZnSOD, the inactivation of certain iron-containing proteins by superoxide, and the mechanisms by which genetic suppressors decrease the superoxide sensitivity of yeast strains lacking CuZnSOD. The second major goal is to discover the relationship(s) between copper and zinc metabolism, superoxide stress, and the metallation state of CuZnSOD. Studies will be directed at understanding the mechanism of copper insertion into CuZnSOD by CCS and at determining the state of metallation of CuZnSOD in different tissues. Understanding how metallation of CuZnSOD is accomplished and how it is regulated in various tissues will help us better understand human antioxidant defenses and thus certain disease states. Overall, this work will advance our understanding of the detailed chemical mechanisms of superoxide stress, the roles of iron, copper, and zinc in the manifestation of superoxide stress, and, ultimately, the role of superoxide stress in human health and aging.