Iodotyrosine deiodinase salvages the iodide from the deiodination of the iodinated tyrosines. Sulfation of tyrosines and carbohydrates occurs within the TGN. Phosphorylation of these tyrosines then initiates intracellular signal transduction processes. These iodinated tyrosines are produced during thyroid hormone biosynthesis. For example, LIFR and OSMR share three homologous tyrosines. It releases iodine, for renewed use, from iodinated tyrosines resulting from catabolism of iodothyronines. The thyroid hormones are released into the bloodstream and the iodinated tyrosines are recycled. The iodination of specific tyrosines yields monoiodotyrosine (MIT) and diiodotyrosine (DIT). However, the breakdown of thyroglobulin produces 6-7 fold more iodinated tyrosines than thyroid hormone. EAT-2 is known to bind to phosphorylated tyrosines on ITSMs and alter cytokine production. Thus the Catalytic tyrosines of TraI and TrwC are amino-terminal rather than carboxy-terminal. Furthermore, SFRP1 is tyrosine-sulfated at two N-terminal tyrosines; this modification is, however, inhibited by heparin. P27 also has three Cdk-inhibited tyrosines at residues 74, 88, and 89. The two main phosphorylation sites on Lck are tyrosines 394 and 505. The phosphorylated ITAMs recruit ZAP-70, which phosphorylates tyrosines in LAT and SLP-76.