PROTEIN PHOSPHORYLATION AND SECRETION AND ETHANOLACTIONS

蛋白质磷酸化、分泌和乙醇反应

• 批准号: 3822995
• 负责人: H C PANT
• 金额: --
• 依托单位: NATIONAL INSTITUTE ON ALCOHOL ABUSE AND ALCOHOLISM
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3822995
• 关键词: axon; brain metabolism; caudate nucleus; cell membrane; central nervous system; cyclic AMP; cyclic nucleoside monophosphate; drug metabolism; ethanol; neural transmission; neurochemistry; neuropharmacology; neurotoxins; phosphorylation; protein kinase; radiotracer; saltwater environment

The phosphorylation of protein has been proposed to be one of the molecular mechanisms involved in cellular regulation. The protein kinases catalyze these phosphorylation reactions. In this investigation, properties of protein kinase activity associated with cell cytoskeletal proteins have been studied in both neuronal and non-neuronal tissues. Extensive studies were carried out to characterize the squid axon neurofilament kinase. These investigations led to conclude that this kinase is a cyclic nucleotide- and calcium-independent protein kinase which is different from casein type I and type II kinases. The axoplasm and neurofilament preparation had no detectable protein kinase inhibitor activity, but strong inhibitor activity, which was not dialyzable but was heat inactivitable, was found in ganglion cells. This inhibitor activity may account for the low phosphorylation activity found in the stellite ganglion cells and may indicate inhibitory regulation of squid axon neurofilament kinase activity in the ganglion cell bodies. In rat brain, the kinase activity is associated with microtubule-associated proteins and phosphorylates them. Effects of ethanol on phosphorylation of microtubule associated protein (MAP 2) were investigated. Ethanol (4-24 mM) increased phosphorylation of MAP 2. In the presence of cAMP or mM ethanol, increased phosphorylation of MAP 2 was observed over control. Much higher phosphorylation of MAP 2 was observed in the presence of both cAMP and ethanol than the sum of phosphorylation of MAP 2 by cAMP and ethanol separately. Kinetic studies of the influence of ethanol on MAP 2 phosphorylation reveal an increased rate of phosphorylation of MAP 2 and a decreased Km in the presence of ethanol. These studies suggest that protein kinase(s) other than cAMP dependent protein kinase are influenced by ethanol and the enzyme(s) phosphorylate at distinct sites on MAP 2. The observation that ethanol affects MAP 2 provides an experimental basis for investigating the effects of ethanol on the structure and function of these cytoskeletal proteins and enzymes.

蛋白质的磷酸化被认为是蛋白质合成的分子机制之一。 参与细胞调节的机制。 蛋白激酶催化 这些磷酸化反应。 在本研究中， 与细胞骨架蛋白相关的蛋白激酶活性 在神经元和非神经元组织中进行了研究。 深入的研究过程 进行了鱿鱼轴突神经丝激酶的特点。 这些研究得出结论，这种激酶是一种环状的 核苷酸和钙非依赖性蛋白激酶，其不同于 酪蛋白I型和II型激酶。 轴浆和神经丝 制剂没有检测到蛋白激酶抑制剂活性，但有很强的 抑制剂活性，其不可透析但热灭活， 在神经节细胞中发现。 这种抑制剂活性可以解释 星状神经节细胞中发现的低磷酸化活性， 表明鱿鱼轴突神经丝激酶活性抑制性调节 在神经节细胞体中。 在大鼠脑中，激酶活性是 与微管相关蛋白质结合并使其磷酸化。 乙醇对微管相关蛋白磷酸化的影响 (MAP（2）进行了调查。 乙醇（4-24 mM）增加了磷酸化， MAP 2. 在cAMP或mM乙醇存在下， 观察到MAP 2超过对照。 MAP 2的磷酸化水平明显高于对照组， 在cAMP和乙醇的存在下观察到， MAP 2分别被cAMP和乙醇磷酸化。 动力学研究 乙醇对MAP 2磷酸化的影响显示， MAP 2的磷酸化速率和Km的降低， 乙醇 这些研究表明，cAMP以外的蛋白激酶 依赖性蛋白激酶受乙醇和酶的影响 在MAP 2上的不同位点磷酸化。 观察到乙醇 影响MAP 2为研究影响提供了实验基础 乙醇对这些细胞骨架蛋白的结构和功能的影响， 内切酶