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MCT8

Meaning

MCT8, or Monocarboxylate Transporter 8, is a highly specific, X-linked transmembrane transport protein that serves as a critical conduit for the active, facilitated uptake and efflux of thyroid hormones across the plasma membrane of target cells. Its expression is particularly high in tissues with a profound dependence on thyroid hormone action, such as the central nervous system, liver, and kidneys. Functional integrity of MCT8 is essential for neurodevelopment and maintaining the tissue-specific availability of triiodothyronine (T3), the metabolically active form of the hormone. Defects in this transporter lead to severe neurological and systemic endocrine dysfunction.