Evidence for a novel thioredoxin-like catalytic property of gonadotropic hormones.
Evidence for a novel thioredoxin-like catalytic property of gonadotropic hormones.
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促性腺激素具有新型硫氧还蛋白样催化特性的证据。
DOI：
10.1126/science.2104678
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
ReichertJr,LE
中科院分区：
文献类型：
--
作者：
Boniface,JJ;ReichertJr,LE
已有研究提出，二硫醇-二硫键交换和氧化还原反应可能在激素诱导的受体激活中起作用。通过对促性腺激素序列的分析，发现促性腺激素的β亚基与硫氧还蛋白活性部位之间存在一个同源的四肽(Cys-Gly-Pro-Cys)。卵泡刺激素的β亚基具有相似的序列(Cys-Gly-Lys-Cys)。硫氧还蛋白是一种普遍存在的蛋白质，作为核苷酸还原酶的电子供体，但它也具有二硫键异构酶活性。通过对还原和变性核糖核酸酶的再激活能力来检测TD的催化活性。在本试验中，纯化的绵羊促卵泡刺激素和牛促黄体生成素制剂的活性分别是∼60和∼的300倍，摩尔基础上是TD。到目前为止，FSH和黄体生成素的这种未知的催化特性可能对了解它们的受体激活和信号转导机制很重要。
It has been proposed that dithiol-disulfide interchange and oxidation-reduction reactions may play a role in hormone-induced receptor activation. Inspection of the sequences of the gonadotropic hormones revealed a homologous tetrapeptide (Cys-Gly-Pro-Cys) between the β subunit of lutropin (LH) and the active site of thioredoxin (TD). The β subunit of follitropin (FSH) has a similar sequence (Cys-Gly-Lys-Cys). Thioredoxin is a ubiquitous protein serving as an electron donor for ribonucleotide reductase, but it also exhibits disulfide isomerase activity. The catalytic activity of TD was assayed by its ability to reactivate reduced and denatured ribonuclease. In this assay, the purified ovine FSH and bovine LH preparations tested were ∼60 and ∼300 times, respectively, as active as TD on a molar basis. This heretofore unsuspected catalytic property of FSH and LH may be important in understanding their mechanism of receptor activation and signal transduction.