Mammalian selenium-containing proteins can be divided into three groups: proteins containing nonspecifically incorporated selenium, specific selenium-binding proteins, and specific selenocysteine-containing selenoproteins. Selenoproteins with known functions identified so far include five glutathione peroxidases, two deiodinases, several thioredoxin reductases, and selenophosphate synthetase 2. Alternative splicing leads to a greater variety of selenoproteins, as was shown in the cases of a specific sperm nuclei glutathione peroxidase and some thioredoxin reductases. Selenoprotein P, selenoprotein W, a 15-kDa selenoprotein, an 18-kDa selenoprotein, and several selenoproteins identified in silico from nucleotide sequence databases were found to contain selenocysteine but their functions are not known. Gel electrophoretic separation of tissue samples from rats labeled in vivo with (75)Se showed the existence of further selenium-containing proteins.

中文翻译：

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含哺乳动物硒的蛋白质。

含哺乳动物硒的蛋白质可分为三类：含非特异性掺入硒的蛋白质，特定的硒结合蛋白和特定的含硒代半胱氨酸的硒蛋白。迄今已鉴定出具有已知功能的硒蛋白包括五个谷胱甘肽过氧化物酶，两个脱碘酶，几种硫氧还蛋白还原酶和硒代磷酸合成酶2。选择性剪接导致硒蛋白种类更多，如特定精子核谷胱甘肽过氧化物酶和某些硫代过氧化物酶的情况所示。还原酶。从核苷酸序列数据库中计算机识别出的硒蛋白P，硒蛋白W，15 kDa硒蛋白，18 kDa硒蛋白和几种硒蛋白被发现含有硒代半胱氨酸，但其功能未知。