{PDOC00925} {PS01205; T4_DEIODINASE} {BEGIN} ***************************************** * Iodothyronine deiodinases active site * ***************************************** Iodothyronine deiodinase (EC 1.97.1.10) (DI) [1,2] is the vertebrate enzyme responsible for the deiodination of the prohormone thyroxine (T4 or 3,5,3',5'- tetraiodothyronine) into the biologically active hormone T3 (3,5,3'- triiodothyronine) and of T3 into the inactive metabolite T2 (3,3'- diiodothyronine). Three types of DI are known. All known DI are proteins of about 250 residues that contain a selenocysteine at their active site. As a signature pattern we selected the best conserved region, it is located in the central part of the enzyme and contains the active site selenocysteine. -Consensus pattern: R-P-L-[IV]-x-[NS]-F-G-S-[CA]-[TS]-[CU]-P-x-F [The C/U is the active site selenocysteine residue] -Sequences known to belong to this class detected by the pattern: ALL. -Other sequence(s) detected in Swiss-Prot: NONE. -Last update: January 2008 / Pattern updated. [ 1] St Germain D.L. (In) Thyroid hormone metabolism: molecular biology and alternative pathways, Wu S.Y., Visser T.J., Eds., pp45-66, CRC Press, Ann Arbor, (1994). [ 2] Davey J.C., Becker K.B., Schneider M.J., St Germain D.L., Galton V.A. "Cloning of a cDNA for the type II iodothyronine deiodinase." J. Biol. Chem. 270:26786-26789(1995). PubMed=7592917 -------------------------------------------------------------------------------- PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see https://prosite.expasy.org/prosite_license.html -------------------------------------------------------------------------------- {END}