MISINCORPORATION OF AMINO ACID ANALOGS IN SELECTED HUMAN AND MURINE PROTEINS

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 氮杂环丁烷-2-羧酸（阿泽）是脯氨酸的低级同系物，环上缺少一个成员，具有毒性和致畸性。 它很容易取代脯氨酸错误地掺入从原核生物到人类的各种物种的蛋白质中。 阿泽以高浓度存在于甜菜的鳞茎中，甜菜占世界蔗糖供应的30%。 甜菜副产品（干浆和糖蜜）含有阿泽;它们被广泛用作奶牛和肉类牲畜的饲料。 蛋白质中富含脯氨酸的片段，例如p53的凋亡结构域，其中28个残基中有11个是脯氨酸，以及髓鞘碱性蛋白的一致表位，其包含序列PRTPPP，是破坏阿泽取代脯氨酸的易受攻击的靶标。暴露于阿泽和多发性硬化症的发生之间存在紧密的地质学、年代学、迁移和地方流行病学相关性。 我们的目的是表征在不同条件下，阿泽错误掺入到选定的小鼠和人蛋白质中的选定蛋白质中的程度。USTag质谱法将用于检测暴露于Aze的小鼠幼仔的组织蛋白中、死于多发性硬化症的患者的脑损伤和非受累区域中以及生活在北美不同地区的人类的血液蛋白中的阿泽置换。这些数据将提供评估阿泽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.