POLYMORPHIC VARIANTS IN HUMAN MUTY

描述(改编自调查者摘要) 最近的研究表明，遗传多态发生在 构成主要DNA修复途径的基因。许多基因中的突变 这些基因可能会导致毒性和突变性增加。在基地内 切除修复途径，修复的主要DNA损伤之一是 氧化损伤的鸟嘌呤，8-oxoG。这种损害的积累已经被 与衰老、癌症、神经变性和动脉粥样硬化相关。其中之一 对于这种错配的有效修复至关重要的基因是 腺嘌呤特异性DNA糖基酶，MutY，在A：8-oxoG去除腺嘌呤 错配。人类MutY同源基因hMYH已被克隆并具有潜在的 鉴定出了多态变异。为了确定功能 这些和其他多态变异在hMYH中的意义，三 独立的实验室走到了一起，有不同但互补的 专业知识，以解决这个问题。第一个具体目标是确定 HMYE基因的更多多态变异，这些研究将是 是在H.Mohrenweiser的实验室进行的。样品的选择将 是NIH预选的代表的子集 占美国总人口的比例。所有16个外显子和内含子-外显子连接将是 对96个基因组DNA样本进行了分析。《特定目标2》侧重于 天然hMYH及其多态变异体的结构与功能分析 这些研究将在S.Lloyd的实验室指导和实施， 根据研究人员的生化和X射线结晶学 原核生物MutY的测定。第三个具体目标，实现于 博尔多的实验室将确定细胞氧化的作用 应激对hMYH的调控和细胞内定位有影响。 不会受到不利影响的多态变体，涉及 催化作用，可能在稳定性和局部性方面受到损害。这些目标 将使用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， 多态筛选和细胞生物学。

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.