Modulation of the phosphatase activity of calcineurin by oxidants and antioxidants in vitro.
Modulation of the phosphatase activity of calcineurin by oxidants and antioxidants in vitro.
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DOI：
10.1046/j.1432-1327.2000.01240.x
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发表时间：
2000-04
期刊：
影响因子：
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通讯作者：
Debbie Sommer;K. L. Fakata;S. Swanson;Paul M. Stemmer
中科院分区：
文献类型：
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作者：
Debbie Sommer;K. L. Fakata;S. Swanson;Paul M. Stemmer
前期研究表明，氧化剂、抗氧化剂和细胞内氧化还原状态调节多种蛋白酪氨酸激酶、蛋白酪氨酸磷酸酶、磷脂酶和转录因子的活性。为了探索丝氨酸/苏氨酸磷酸酶钙调磷酸酶的氧化还原调节，我们在体外研究了多种氧化剂和抗氧化剂对钙调磷酸酶活性的影响。氧化剂过氧化氢、超氧化物和二硫化谷胱甘肽以剂量依赖性方式抑制钙调神经磷酸酶的磷酸酶活性。与未处理的对照相比，纯化的钙调神经磷酸酶与抗氧化剂抗坏血酸、抗坏血酸2-磷酸、α-硫辛酸、N-乙酰基-L-半胱氨酸和谷胱甘肽一起孵育增加了磷酸酶活性。相比之下，其他几种常用的抗氧化剂，包括丁基羟基甲苯、丁基羟基苯甲醚、TEMPOL（4-羟基-2,2,6,6-四甲基哌啶-N-氧基）、Trolox（6-羟基-2,5,7,8-四甲基-苯并二氢吡喃-2-羧酸）和二氢硫辛酸可能通过促氧化机制降低了纯化的钙调神经磷酸酶的活性。尽管抗氧化剂吡咯烷二硫代氨基甲酸盐增加了纯化的钙调磷酸酶的活性，但它显着抑制了粗成纤维细胞裂解物中存在的钙调磷酸酶的活性。这些结果支持并扩展了氧化还原因子调节钙调神经磷酸酶的磷酸酶活性的假设，并表明有必要进行进一步的体内研究。
Previous research has indicated that oxidants, antioxidants and the intracellular redox state regulate the activities of a variety of protein tyrosine kinases, protein tyrosine phosphatases, phospholipases and transcription factors. In order to explore the redox regulation of the serine/threonine phosphatase calcineurin, we have investigated the effects of a variety of oxidants and antioxidants on calcineurin phosphatase activity in vitro. The oxidants hydrogen peroxide, superoxide and glutathione disulfide inhibited the phosphatase activity of calcineurin in a dose-dependent manner. Incubation of purified calcineurin with the antioxidants ascorbate, ascorbate 2-phosphate, alpha-lipoic acid, N-acetyl-L-cysteine and glutathione increased phosphatase activity relative to untreated controls. In contrast, several other commonly used antioxidants, including butylated hydroxytoluene, butylated hydroxyanisole, TEMPOL (4-hydroxy-2,2,6, 6-tetramethylpiperidine-N-oxyl), Trolox (6-hydroxy-2,5,7, 8-tetramethyl-chroman-2-carboxylic acid) and dihydrolipoic acid decreased the activity of purified calcineurin, possibly through prooxidative mechanisms. Although the antioxidant pyrrolidine dithiocarbamate increased the activity of purified calcineurin, it significantly inhibited the activity of calcineurin present in crude fibroblast lysates. These results support and extend the hypothesis that redox factors modulate the phosphatase activity of calcineurin and suggest that further in vivo studies are warranted.