Type I iodothyronine deiodinase (DIO1)

Responsible for the deiodination of T4 (3,5,3',5'- tetraiodothyronine) into T3 (3,5,3'-triiodothyronine) and of T3 into T2 (3,3'-diiodothyronine).

Plays a role in providing a source of plasma T3 by deiodination of T4 in peripheral tissues like liver and kidney.

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