ROLE OF CYCLIC ADP-RIBOSE IN CALCIUM DISPOSITION IN NG108-15 CELLS

拟议研究的总体目标是确定 环腺苷二磷酸核糖（cADPR）在钙稳态调节中的作用 NG108细胞，神经元细胞系。cADPR是一种天然存在的 核苷酸被发现是一种有效的钙释放介质， 细胞内储存。 建议的具体目标是：（1） 表征NG 108细胞中的细胞内钙池，（2）以 表征NG108细胞中cADPR合成和降解酶， (3)表征NG108细胞中的cADPR结合蛋白，和（4） 检测NG108中内源性cADPR水平的调节 细胞 将探测NG108细胞中的细胞内钙池 使用去污剂透化的细胞或纯化的微粒体， 其特征在于cADPR、咖啡因和肌醇 释放储存的钙。 的表征 合成、降解和结合cADPR的蛋白质将通过以下方式实现： 它们的亚细胞定位、调节和纯化的研究。 细胞内cADPR浓度的调节将是 通过在各种已知升高的条件下测量cADPR来检查 胞内钙 细胞内浓度的调节 钙的吸收是所有细胞中的关键过程。在神经元细胞中， 钙的变化在许多神经元中起着重要作用， 包括神经递质的释放， 细胞骨架、基因表达和许多代谢事件。 最近 有证据表明，cADPR可能是内源性调节剂， 钙诱导的钙释放，并通过类似于 咖啡因 咖啡因是中枢神经的强力兴奋剂 系统，可能是因为这个动作，是最广泛的 毒品在世界上。 咖啡因刺激大脑的机制 中枢神经系统尚未完全了解。 由于cADPR出现 是咖啡因敏感细胞释放钙的内源性调节剂， cADPR功能和代谢的系统研究 细胞应该提供有关刺激中枢神经系统的有用信息。 神经系统

The overall objective of the proposed research is to define the role of cyclic ADP-ribose (cADPR) in the regulation of calcium homeostasis in NG108 cells, a neuronal cell line. cADPR is a naturally occurring nucleotide found to be a potent mediator of calcium release from intracellular stores. The specific aims of the proposal are: (1) to characterize intracellular calcium pools in NG 108 cells, (2) to characterize the cADPR synthetic and degradative enzymes in NG108 cells, (3) to characterize the cADPR binding protein(s) in NG108 cells, and (4) to examine the regulation of the endogenous level of cADPR in NG108 cells. The intracellular pools of calcium in NG108 cells will be probed using detergent permeabilized cells or purified microsomes and characterized in terms of the ability of cADPR, caffeine and inositol trisphosphate to release stored calcium. The characterization of the proteins that synthesize, degrade and bind cADPR will be achieved through studies on their subcellular localization, regulation, and purification. The regulation of the intracellular concentration of cADPR will be examined by measuring cADPR under a variety of conditions known to raise intracellular calcium. The regulation of the intracellular concentration of calcium is a critical process in all cells . In neuronal cells, changes in calcium play an important role in a number of neuronal processes including neurotransmitter release, changes in the cytoskeleton, gene expression and a number of metabolic events. Recent evidence suggests that cADPR may be the endogenous modulator of calcium-induced calcium release and act through a mechanism similar to caffeine. Caffeine is a powerful stimulant of the central nervous system, and probably because of this action, is one of the most widely used drugs in the world. The mechanism by which caffeine stimulates the central nervous system is not completely understood. Since cADPR appears to be the endogenous modulator of calcium release from caffeine-sensitive stores, a systematic study of cADPR function and metabolism in neuronal cells should provide useful information on stimulation of the central nervous system.