POLYMORPHIC VARIANTS IN HUMAN MUTY

人类突变体的多态性变异

• 批准号: 6372416
• 负责人: AMANDA K MCCULLOUGH
• 金额: $ 22.12万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-05-01 至 2003-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6372416
• 关键词: DNA damage; DNA repair; Escherichia coli; HeLa cells; N glycosidase; cell population study; enzyme activity; enzyme structure; genetic polymorphism; genetic screening; human tissue; nucleic acid sequence; oxidative stress; polymerase chain reaction; protein localization; protein purification; protein structure function; site directed mutagenesis

DESCRIPTION (Adapted From the Investigator's Abstract) Recent studies have demonstrated that genetic polymorphisms occur within the genes that comprise the major DNA repair pathways. Mutations within many of these genes can lead to increased toxicity and mutagenicity. Within the base excision repair pathway, one of the primary DNA lesions that is repaired is an oxidatively damaged guanine, 8-oxoG. The accumulation of this lesion has been correlated with aging, cancer, neurodegeneration, and atherosclerosis. One of the genes that is central to the efficient repair of this mismatch is the adenine-specific DNA glycosylase, MutY, that removes adenine at A:8-oxoG mispairs. The human MutY homolog, hMYH, has been cloned and potential polymorphic variants identified. In order to determine the functional significance of these and additional polymorphic variants in hMYH, three independent laboratories have come together with diverse but complementary expertise, to address this question. The first specific aim is to identify additional polymorphic variants in the hMYE gene and these studies will be carried out in the laboratory of H. Mohrenweiser. The choice of samples will be a subset of those that have been preselected by NIH as being representative of the U.S. population. All 16 exons and intron-exon junctions will be analyzed from 96 genomic DNA samples. Specific aim 2 focuses on the structure-function analysis of native hMYH and its polymorphic variants. These studies will be guided and implemented in the laboratory of S. Lloyd, based on the investigator's biochemical and x-ray crystallographic determination of the prokaryotic MutY. The third specific aim, carried out in the laboratory of I. Boldogh, will ascertain the role that cellular oxidative stress has on the regulation and intracellular localization of hMYH. Polymorphic variants that are not affected adversely, with respect to catalysis, may be impaired in stabilization and localization. These goals will be accomplished using a multidisciplinary collaborative approach utilizing expertise in DNA repair enzymology, structure-function analysis, polymorphic screening, and cell biology.

描述（改编自研究者的摘要） 最近的研究表明，遗传多态性发生在 构成主要 DNA 修复途径的基因。 许多内的突变 这些基因可导致毒性和致突变性增加。 基地内 切除修复途径，被修复的主要 DNA 损伤之一是 氧化损伤的鸟嘌呤，8-oxoG。 这种损伤的累积 与衰老、癌症、神经退行性变和动脉粥样硬化有关。 之一 对于有效修复这种错配至关重要的基因是 腺嘌呤特异性 DNA 糖基化酶 MutY，可去除 A:8-oxoG 处的腺嘌呤 错配。 人类 MutY 同源物 hMYH 已被克隆并具有潜力 鉴定出多态性变体。 为了确定函数 hMYH 中这些和其他多态性变体的重要性，三个 独立的实验室汇集了不同但互补的实验室 专业知识，解答这个问题。 第一个具体目标是确定 hMYE 基因中的其他多态性变异，这些研究将 在 H. Mohrenweiser 的实验室中进行。 样本的选择将 是 NIH 预先选定的具有代表性的子集 的美国人口。 所有 16 个外显子和内含子-外显子连接点将 对 96 个基因组 DNA 样本进行了分析。 具体目标 2 侧重于 天然 hMYH 及其多态性变体的结构功能分析。 这些研究将在 S. Lloyd 实验室指导和实施， 基于研究者的生化和 X 射线晶体学 原核MutY的测定。 第三个具体目标，实现于 I. Boldogh 的实验室将确定细胞氧化的作用 应激对 hMYH 的调节和细胞内定位有影响。 就以下方面而言，不会受到不利影响的多态性变体 催化，可能会损害稳定性和定位。 这些目标 将通过多学科协作方法来完成 利用 DNA 修复酶学、结构功能分析方面的专业知识， 多态性筛选和细胞生物学。