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Selenoprotein

Any of ~25 human proteins containing selenocysteine (Sec, the 21st amino acid) encoded by UGA codons recoded via SECIS elements, including glutathione peroxidases, thioredoxin reductases, and iodothyronine deiodinases.

Selenoprotein synthesis prioritization under low selenium intake explains why deficiency manifestations vary by enzyme. Glutathione peroxidase (GPX) reduces hydroperoxides, iodothyronine deiodinases (DIO1-3) activate/inactivate thyroid hormones, and selenoprotein P transports selenium. Severe deficiency causes Keshan disease (cardiomyopathy) and Kashin-Beck disease (osteoarthropathy). RDA is set at 55 μg/d based on plasma GPX activity.

How one textbook covers it

  • Modern Nutrition in Health and Disease, 12th ed. — Ch 15: Selenium

    Selenoprotein synthesis prioritization under low selenium intake explains why deficiency manifestations vary by enzyme. Glutathione peroxidase (GPX) reduces hydroperoxides, iodothyronine deiodinases (DIO1-3) activate/inactivate thyroid hormones, and selenoprotein P transports selenium. Severe deficiency causes Keshan disease (cardiomyopathy) and Kashin-Beck disease (osteoarthropathy). RDA is set at 55 μg/d based on plasma GPX activity.

Related terms

Glutathione peroxidase, Selenium, Thyroid hormone