MISINCORPORATION OF AMINO ACID ANALOGS IN SELECTED HUMAN AND MURINE PROTEINS

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 氮杂环丁烷-2-羧酸(AZE)是一种有毒的致畸化合物，是脯氨酸的低同系物，其环上缺少一个成员。它很容易被错误地结合到从原核生物到人类的各种物种的蛋白质中，而不是脯氨酸。AZE在甜菜的鳞茎中含量很高，占世界蔗糖供应的30%。甜菜副产品(干果肉和糖蜜)含有AZE；它们被广泛用作奶制品和肉畜的饲料。蛋白质中富含脯氨酸的部分，如P53的凋亡区，其中28个残基中有11个是Pro，以及髓鞘碱性蛋白的共识表位，包含PRTPPP序列，是破坏Aze替代Pro的脆弱靶点。暴露于AZE与多发性硬化症的发生有密切的地质学、年代学、迁移性和地方性流行病学相关性。 我们的目标是在不同的条件下，研究不同条件下Aze在选定的小鼠和人类蛋白中错掺的程度。UStag质谱学方法将被用于检测暴露于Aze的小鼠的组织蛋白、多发性硬化症患者大脑的病变和非受累区域以及生活在北美不同地区的人类的血液蛋白中的Aze替换。这些数据将提供评估AZE在疾病发病机制中的作用所需的信息。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Azetidine-2-carboxylic acid (Aze), a toxic and teratogenic compound, is the lower homologue of proline, lacking one member in its ring. It is readily misincorporated in place of proline into the proteins of species ranging from prokaryotes to humans. Aze is present in high concentration in the bulbs of sugar beets, which account for 30% of the world's sucrose supply. Sugar beet byproducts (dried pulp and molasses) contain Aze; they are widely used as feed for dairy and meat livestock. Proline-rich stretches in proteins, such as the apoptotic domain of p53, in which 11 of 28 residues are prolyls, and the consensual epitope of myelin basic protein, which embraces the sequence PRTPPP, are vulnerable targets for corrupting substitution of Aze for proline. There are tight geological, chronological, migrational, and enzootic epidemiologic correlations between exposure to Aze and the occurrence of multiple sclerosis. We aim to characterize the extent of Aze misincorporation in selected proteins in selected mice and human proteins under different conditions. The UStag mass spectrometry approach will be used to detect Aze substitutions in the tissue proteins of Aze-exposed murine pups, in the lesions and in non-involved regions of brains from patients who died with multiple sclerosis, and in the blood proteins of humans living in various regions of North America. These data will provide information needed to assess the role of Aze in the pathogenesis of disease.