Pendrin and anoctamin as mediators of apical iodide efflux in thyroid cells

Autor(es)

Silveira, Jamile C. ^{[1, 2]} ; Kopp, Peter A. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biomed Sci, Dept Physiol & Biophys, Sao Paulo - Brazil

^[2] Northwestern Univ, Feinberg Sch Med, Div Endocrinol Metab & Mol Med, Chicago, IL 60611 - USA

• Tipo de documento: Artigo de Revisão
• Fonte: CURRENT OPINION IN ENDOCRINOLOGY DIABETES AND OBESITY; v. 22, n. 5, p. 374-380, OCT 2015.
• Citações Web of Science: 9

Resumo

Purpose of reviewThyroid hormones are essential for normal development, growth, and metabolism. Their synthesis occurs in thyroid follicles and requires an adequate iodide supply and a sequence of regulated biochemical steps. The uptake of iodide into thyrocytes is well characterized, but its efflux at the apical membrane is poorly understood. This review discusses potential mechanisms underlying iodide efflux with emphasis on recent developments and controversies.Recent findingsThe functional characterization of pendrin (PDS/SLC26A4), a multifunctional anion exchanger, suggested that it could be involved in mediating iodide efflux. This is supported by the phenotype of patients with Pendred syndrome (deafness, goiter, partial iodide organification defect), which is caused by biallelic mutations in the SLC26A4 gene, as well as functional studies. However, apical iodide efflux is also possible in the absence of pendrin, implicating the presence of at least another channel. Recently, Anoctamin 1 (TMEM16A), a calcium-activated anion channel has been identified at the apical membrane of thyrocytes and functional studies suggest that it may play a predominant role in mediating iodide efflux.SummaryAnoctamin and pendrin are two plausible candidates as mediators of apical iodide efflux. Their relative affinity for iodide and their exact physiological role await, however, further characterization. (AU)

• Processo FAPESP: 10/05503-2 - Efeito da administração aguda de iodo sobre a expressão e a atividade do promotor do gene da pendrina: estudo in vivo e in vitro
• Beneficiário: Jamile Calil Silveira
• Modalidade de apoio: Bolsas no Brasil - Doutorado