REGULATION OF CYCLIC ADP RIBOSE SIGNALING SYSTEM

环状 ADP 核糖信号系统的调控

• 批准号: 6338716
• 负责人: TIMOTHY Francis WALSETH
• 金额: $ 40.85万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-22 至 2001-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6338716
• 关键词: ADP ribosylation; PC12 cells; adenosine diphosphate; binding proteins; biological signal transduction; calcium channel; calcium flux; cell line; genetic regulation; laboratory rat; nicotinamide adenine dinucleotide; protein purification; protein sequence; radioimmunoassay; ribose

The overall objectives of the proposed research are to gain insight into the mechanism by which cyclic ADP-ribose (cADPR) mobilizes calcium from intracellular stores and to elucidate the mechanisms by which cADPR levels are regulated in mammalian cells. cADPR is a naturally occurring metabolite of beta-nicotinamide adenine dinucleotide )beta-NAD) that has been found to mobilize calcium from intracellular stores in a variety of cell types. The specific aims are: (1) to identify and characterize cADPR binding proteins in mammalian systems, (2) to examine the regulation of endogenous levels of cADPR in mammalian systems, and (3) to characterize the mechanisms involved in the regulation of cADPR metabolic enzymes. cADPR binding proteins will be studied by conventional binding as well as by photoaffinity labeling techniques. 3-deaza-cADPR, a potent, non- hydrolyzable analog of cADPR, has recently been developed, and will be an important probe in the examination of proteins to which cADPR interacts. The regulation of endogenous levels of cADPR will be examined in several mammalian cell lines using a radioimmunoassay for cADPR developed in this laboratory. Particular attention will be focused on agents that are known to alter intracellular calcium concentrations, either through calcium influx or by mobilization of interal stores of calcium. The mechanism(s) by which cADPR levels are regulated will be examined by characterizing the enzymes responsible for the synthesis (ADP-ribosyl cyclase) and degradation (cADPR hydrolase) from systems shown to have alterations in cADPR levels. The regulation of the intracellular concentration of calcium is a critical process in all cells. Calcium plays an important role in a number of processes, including neurotransmitter release, cytoskeleton changes, muscle contraction, gene expression, etc. Accumulating evidence suggests that cADPR may be the endogenous regulator of calcium induced- calcium release (CICR) through ryanodine receptor type calcium release channels. cADPR appears to increase the sensitivity of CICR to calcium ions in a manner very similar to caffeine. Caffeine has many physiological actions and is one of the most socially abused drugs in the world. The proposed studies should provide useful information on the role cADPR plays in the regulation of calcium homeostasis and may also provide valuable insight into some of caffeine's biological actions.

拟议研究的总体目标是洞悉 环状ADP-核糖（CADPR）动员钙的机制 细胞内存储并阐明CADPR水平的机制 在哺乳动物细胞中受调节。 CADPR是自然发生的 β-尼古丁酰胺腺苷二核苷酸的代谢物）β-nad） 发现在各种细胞内存储中动员钙 细胞类型。具体目的是：（1）识别和表征CADPR 哺乳动物系统中的结合蛋白，（2）检查调节 哺乳动物系统中的内源性CADPR水平，（3）表征 CADPR代谢酶调节涉及的机制。 CADPR结合蛋白将通过常规结合以及 通过照片亲和力标签技术。 3-deaza-cadpr，有效的，非 - CADPR的可水解类似物最近已经开发，将是一个 CADPR相互作用的蛋白质检查中的重要探针。 在几个 在此开发的CADPR的哺乳动物细胞系使用放射免疫分子 实验室。特别关注的是已知的代理 通过钙改变细胞内钙浓度 涌入或通过动员钙的储存。机制 通过表征该CADPR级别的调节水平将进行检查 负责合成的酶（ADP-核糖基环酶）和 降解（CADPR水解酶）来自显示有变化的系统 CADPR水平。钙的细胞内浓度的调节 在所有细胞中都是关键过程。钙在A中起重要作用 过程数量，包括神经递质释放，细胞骨架 变化，肌肉收缩，基因表达等。积累证据 表明CADPR可能是钙诱导的内源性调节剂 钙释放（CICR）通过ryanodine受体型钙释放 频道。 CADPR似乎增加了CICR对钙的敏感性 离子的方式与咖啡因非常相似。咖啡因有许多生理 行动，是世界上最受社会滥用的药物之一。这 拟议的研究应提供有关CADPR扮演角色的有用信息 在钙稳态的调节中，也可能提供有价值的 深入了解咖啡因的一些生物学作用。