Redox control of caspase-3 activity by thioredoxin and other reduced proteins
Redox control of caspase-3 activity by thioredoxin and other reduced proteins
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DOI：
10.1006/bbrc.1999.1908
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发表时间：
2000-02-05
影响因子：
3.1
通讯作者：
Powis, G
中科院分区：
文献类型：
--
作者：
Baker, A;Dos Santos, B;Powis, G
半胱天冬酶是在细胞凋亡的执行阶段起关键作用的半胱氨酸蛋白酶。活性位点半胱氨酸残基必须被还原以获得胱天蛋白酶活性。硫氧还蛋白是催化半胱氨酸残基还原的氧化还原蛋白。我们已经检查了各种重组人硫氧还蛋白激活半胱天冬酶-3的能力。通过还原型硫氧还蛋白-1活化胱天蛋白酶-3的EC 50为2.5 μ M，通过还原型谷胱甘肽1.0 mM和通过二硫苏糖醇3.5 mM。催化位点氧化还原失活的突变体硫氧还蛋白-1在活化胱天蛋白酶-3中几乎与硫氧还蛋白-1一样活跃。半胱天冬酶的活化与硫氧还蛋白中还原半胱氨酸残基的数量相关。减少胰岛素和血清白蛋白在激活半胱天冬酶-3方面与硫氧还蛋白-1在摩尔基础上一样有效。因此，半胱天冬酶-3激活不是硫氧还蛋白的特异性作用，而是其他还原蛋白共有的性质。(C)北京大学出版社.
Caspases are cysteine proteinases that play a critical role in the execution phase of apoptosis. The active site cysteine residue must be reduced for caspase activity. Thioredoxins are redox proteins that catalyze the reduction of cysteine residues. We have examined the ability of various recombinant human thioredoxins to activate caspase-3. The EC50 for caspase-3 activation by reduced thioredoxin-1 was 2.5 mu M, by reduced glutathione 1.0 mM and by dithiothreitol 3.5 mM. A catalytic site redox-inactive mutant thioredoxin-1 was almost as active as thioredoxin-1 in activating caspase-3. Caspase activation was shown to correlate with the number of reduced cysteine residues in the thioredoxins. Reduced insulin and serum albumin were as effective on a molar basis as thioredoxin-1 in activating caspase-3. Thus, caspase-3 activation its not a specific effect of thioredoxins but is a property shared by other reduced proteins. (C) 2000 Academic Press.