Iodotyrosine dehalogenase 1 (DEHAL1) is a transmembrane protein involved in the recycling of iodide close to the thyroglobulin iodination site

SPECIFIC AIMSIn the thyroid, iodotyrosine dehalogenase acts on the mono (L-MIT) and diiodotyrosines (L-DIT) released during thyroglobulin hydrolysis and liberates iodide, which can then reenter hormone-producing pathways. This deiodinating activity is so efficient that only negligible amounts of iodotyrosines are secreted by the thyroid. It has been reported that iodotyrosine deiodination occurs predominantly in the microsomes and is mediated by NADPH. Recently, two cDNAs, 7,401 and 7,513-base-pairs long, and encoding proteins with a conserved nitroreductase domain were published in GenBank as iodotyrosine dehalogenase 1 (DEHAL1) and iodotyrosine dehalogenase 1B (DEHAL1B). Because the DEHAL1 protein has a complete nitroreductase domain, we chose to study the localization and the activity of this isoform first.PRINCIPAL FINDINGS1. DEHAL1 belongs to the nitroreductase familyA 7401 base pair cDNA, isolated from human thyroid was published in GenBank as iodotyrosine dehalogenase protein mRNA (accession #AY259...