Iodothyronine deiodinases

Iodothyronine deiodinases form a subfamily of the deiodinases , they play a crucial role in the activation and inactivation of iodothyronines , thyronamines and iodothyroacetates . Iodothyronine deiodinases are selenium-dependent enzymes .

Types

Most vertebrates have three iodothyronine deiodinases, two activating ( 5'-deiodinases ) and one inactivating ( 5-deiodinase ).

Type	gene	localization	function
Type 1 (D1)	DIO1	including liver and kidney	Deiodination of both rings (5-deiodination and 5'-deiodination)
Type 2 (D2)	DIO2	Heart muscle , skeletal muscle , central nervous system , adipose tissue , thyroid , pituitary gland	Outer ring deiodization (5'-deiodization)
Type 3 (D3)	DIO3	Fetal tissue and placenta	Inner ring deiodization (5-deiodization)

mechanism

Deiodinases modify iodothyronines, thyronamines and iodothyroacetates by removing one iodine atom each from the inner ring (5-position) or outer ring (5'-position). In this way, thyroid hormones can be inactivated or activated.

Reactions catalyzed by deiodinases

Regulation of deiodinase activity

literature

1. ↑ B. Gereben, AM Zavacki, S. Ribich, BW Kim, SA Huang, WS Simonides, A. Zeöld, AC Bianco: Cellular and molecular basis of deiodinase-regulated thyroid hormone signaling. In: Endocr Rev . 29 (7), Dec 2008, pp. 898-938. doi: 10.1210 / er.2008-0019 . PMID 18815314
2. ^ National Academy of Hypothyroidism , Deiodinases