Selenoproteins of the thyroid gland: expression, localization and possible function of glutathione peroxidase 3
-
Cornelia Schmutzler
Abstract
The thyroid gland has an exceptionally high selenium content, even during selenium deficiency. At least 11 selenoproteins are expressed, which may be involved in the protection of the gland against the high amounts of H2O2 produced during thyroid hormone biosynthesis. As determined here by in situ hybridization and Northern blotting experiments, glutathione peroxidases (GPx) 1 and 4 and selenoprotein P were moderately expressed, occurring selectively in the follicular cells and in leukocytes of germinal follicles of thyroids affected by Hashimoto's thyroiditis. Selenoprotein 15 was only marginally expressed and distributed over all cell types. GPx3 mRNA was exclusively localized to the thyrocytes, showed the highest expression levels and was down-regulated in 5 of 6 thyroid cancer samples as compared to matched normal controls. GPx3 could be extracted from thyroidal colloid by incubation with 0.5% sodium dodecyl sulfate indicating that this enzyme is (i) secreted into the follicular lumen and (ii) loosely attached to the colloidal thyroglobulin. These findings are consistent with a role of selenoproteins in the protection of the thyroid from possible damage by H2O2. Particularly, GPx3 might use excess H2O2 and catalyze the polymerization of thyroglobulin to the highly cross-linked storage form present in the colloid.
©2007 by Walter de Gruyter Berlin New York
Artikel in diesem Heft
- Selenoproteins – biochemistry and clinical relevance
- Selenium in mammalian spermiogenesis
- Selenium in chemistry and biochemistry in comparison to sulfur
- Molecular biology of glutathione peroxidase 4: from genomic structure to developmental expression and neural function
- Physiological role of phospholipid hydroperoxide glutathione peroxidase in mammals
- Activation of the glutathione peroxidase 2 (GPx2) promoter by β-catenin
- Effect of age on sexually dimorphic selenoprotein expression in mice
- Post-translational processing of selenoprotein P: implications of glycosylation for its utilisation by target cells
- Selenoproteins of the thyroid gland: expression, localization and possible function of glutathione peroxidase 3
- Towards understanding selenocysteine incorporation into bacterial proteins
- Glutathione- and thioredoxin-related enzymes are modulated by sulfur-containing chemopreventive agents
- B- and T-cell-specific inactivation of thioredoxin reductase 2 does not impair lymphocyte development and maintenance
- Effect of selenium on thioredoxin reductase activity in Txnrd1 or Txnrd2 hemizygous mice
- Influence of pH and flanking serine on the redox potential of S-S and S-Se bridges of Cys-Cys and Cys-Sec peptides
- An essential role for Pin1 in Xenopus laevis embryonic development revealed by specific inhibitors
- Glucocorticoid receptor-mediated expression of kallikrein 10 in human breast cancer cell lines
Artikel in diesem Heft
- Selenoproteins – biochemistry and clinical relevance
- Selenium in mammalian spermiogenesis
- Selenium in chemistry and biochemistry in comparison to sulfur
- Molecular biology of glutathione peroxidase 4: from genomic structure to developmental expression and neural function
- Physiological role of phospholipid hydroperoxide glutathione peroxidase in mammals
- Activation of the glutathione peroxidase 2 (GPx2) promoter by β-catenin
- Effect of age on sexually dimorphic selenoprotein expression in mice
- Post-translational processing of selenoprotein P: implications of glycosylation for its utilisation by target cells
- Selenoproteins of the thyroid gland: expression, localization and possible function of glutathione peroxidase 3
- Towards understanding selenocysteine incorporation into bacterial proteins
- Glutathione- and thioredoxin-related enzymes are modulated by sulfur-containing chemopreventive agents
- B- and T-cell-specific inactivation of thioredoxin reductase 2 does not impair lymphocyte development and maintenance
- Effect of selenium on thioredoxin reductase activity in Txnrd1 or Txnrd2 hemizygous mice
- Influence of pH and flanking serine on the redox potential of S-S and S-Se bridges of Cys-Cys and Cys-Sec peptides
- An essential role for Pin1 in Xenopus laevis embryonic development revealed by specific inhibitors
- Glucocorticoid receptor-mediated expression of kallikrein 10 in human breast cancer cell lines
