Cellular and Molecular Basis of Deiodinase-Regulated Thyroid Hormone Signaling1

The iodothyronine deiodinases initiate or terminate thyroid hormone action and therefore are critical for the biological effects mediated by thyroid hormone. Over the years, research has focused on their role in preserving serum levels of the biologically active molecule T 3 during iodine deficiency. More recently, a fascinating new role of these enzymes has been unveiled. The activating deiodinase (D2) and the inactivating deiodinase (D3) can locally increase or decrease thyroid hormone signaling in a tissue-and temporal-specific fashion, independent of changes in thyroid hormone serum concentrations. This mechanism is particularly relevant be-cause deiodinase expression can be modulated by a wide variety of…

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  Exelixis
• HS
  Hungarian Scientific Research Fund
• MT
  Magyar Tudományos Akadémia