Effects of Lead on Calcium-Binding Proteins in Rats

描述(由申请人提供)：拟议研究的主要长期目标是[1]测试铅与C2和Annexin家族的钙结合蛋白相互作用的假设，以及[2]确定这些钙结合家族的基因和蛋白质在大鼠铅暴露后受到调控。铅中毒在美国仍然是一个普遍存在的问题，至少有5%的儿童受到影响。这项拟议的研究旨在阐明铅中毒的分子机制。以前的研究表明，铅与C2结构域家族的蛋白(如蛋白激酶C和突触素)和膜联蛋白之间存在着有效的相互作用。此外，细胞暴露于铅可以调节编码钙结合膜联蛋白的基因的表达。这项提议的四个具体目标是[1]测量铅与C2结构域和膜联蛋白家族蛋白的相互作用，以确定铅的可能靶标。[2]检测染铅大鼠脑、肾、肝组织的基因表达。这个体内模型可能揭示铅暴露是否差异地调节编码钙结合蛋白的基因的表达。[3]将基因表达研究扩展到特性良好的细胞系(星形胶质细胞、PC12细胞、成纤维细胞和正常大鼠肾脏细胞)。这些研究将补充体内模型的基因表达测量。[4]将基因表达数据存储到可公开访问的数据库中。总而言之，这些研究可能揭示哪些钙结合蛋白与铅相互作用，哪些编码钙结合蛋白的基因受到铅暴露的调控。

DESCRIPTION (provided by applicant): The major long-term objectives of the proposed research are [1] to test the hypothesis that lead interacts with calcium binding proteins of the C2 and annexin families, and [2] to identify genes and proteins of these calcium-binding families that are regulated following lead exposure of rats. Lead poisoning remains a pervasive problem in the United States, affecting at least 5% of all children. The proposed research is intended to elucidate molecular mechanisms underlying lead toxicity. Previous studies have demonstrated potent interactions between lead and proteins of the C2 domain family (e.g. protein kinase C and synaptotagmin) and annexins. Furthermore, lead exposure of cells has been shown to regulate the expression of genes encoding calcium-binding annexins. The four specific aims of this proposal are [1] to measure the interactions of lead with proteins of the C2 domain and annexin families, in order to determine the possible targets of lead. [2] To measure gene expression in the brain, kidney and liver of lead-exposed rats. This in vivo model may reveal whether lead exposure differentially regulates the expression of genes encoding calcium-binding proteins. [3] To extend gene expression studies to well characterized cell lines (astrocytes, PC12 cells, fibroblasts and normal rat kidney cells). These studies will complement gene expression measurements from the in vivo model. [4] To deposit gene expression data into a publicly accessible database. Together these studies may reveal which calcium binding proteins interact with lead, and which genes encoding calcium-binding proteins are regulated by lead exposure.