PROTEIN PHOSPHORYLATION AND SECRETION AND ETHANOL ACTIONS

蛋白质的磷酸化被认为是蛋白质合成的重要途径之一。 参与细胞调控的分子机制。 的 蛋白激酶催化这些磷酸化反应。 在这 研究，与蛋白激酶活性相关的性质， 细胞骨架蛋白已在神经元和 非神经元组织。 进行了广泛的研究， 描述鱿鱼轴突神经丝激酶。 这些 研究得出结论，这种激酶是一种环状的 非核苷酸和钙依赖性蛋白激酶， 不同于酪蛋白I型和II型激酶。 轴浆 而神经丝制备物中未检测到蛋白激酶 抑制剂活性，但强抑制剂活性，这不是 透析，但热灭活，发现在神经节细胞。 这种抑制剂活性可以解释低磷酸化 星状神经节细胞中发现的活性， 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 与微管相关蛋白相关， 磷酸化它们。 乙醇对磷酸化的影响 微管相关蛋白（MAP 2）。 乙醇（4-24 mM）增加MAP 2的磷酸化。 在 cAMP或mM乙醇的存在， 观察到MAP 2超过对照。 更高的磷酸化 在cAMP和乙醇存在下，观察到MAP 2的增加， MAP 2被cAMP和乙醇磷酸化总和 分开 乙醇对MAP 2影响的动力学研究 磷酸化显示磷酸化的速率增加， MAP 2和降低Km在乙醇的存在下。 这些 研究表明，除了cAMP依赖性蛋白激酶， 蛋白激酶受乙醇和酶的影响 在MAP 2上的不同位点磷酸化。 的观察结果 乙醇对MAP 2的影响为 研究乙醇对结构和功能的影响 这些细胞骨架蛋白质和酶。

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 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.