Members of the SLC16 family may be divided into subfamilies on the basis of substrate selectivities, particularly lactate (e.g. L-lactic acid), pyruvic acid and ketone bodies, as well as aromatic amino acids. Topology modelling suggests 12 TM domains, with intracellular termini and an extended loop at TM 6/7.

The proton-coupled monocarboxylate transporters (monocarboxylate transporters 1, 4, 2 and 3) allow transport of the products of cellular metabolism, principally lactate (e.g. L-lactic acid) and pyruvic acid.

MCT1 and MCT2, but not MCT3 and MCT4, are inhibited by CHC, which also inhibits members of the mitochondrial transporter family, SLC25.

MCT5-MCT7, MCT9 and MCT11-14 are regarded as orphan transporters.

* Key recommended reading is highlighted with an asterisk

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Friesema EC, Visser WE, Visser TJ. (2010) Genetics and phenomics of thyroid hormone transport by MCT8. Mol Cell Endocrinol, 322 (1-2): 107-13. [PMID:20083155]

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Heuer H, Visser TJ. (2009) Minireview: Pathophysiological importance of thyroid hormone transporters. Endocrinology, 150 (3): 1078-83. [PMID:19179441]

Jansen J, Friesema EC, Milici C, Visser TJ. (2005) Thyroid hormone transporters in health and disease. Thyroid, 15 (8): 757-68. [PMID:16131319]

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Morris ME, Felmlee MA. (2008) Overview of the proton-coupled MCT (SLC16A) family of transporters: characterization, function and role in the transport of the drug of abuse gamma-hydroxybutyric acid. AAPS J, 10 (2): 311-21. [PMID:18523892]

van der Deure WM, Peeters RP, Visser TJ. (2010) Molecular aspects of thyroid hormone transporters, including MCT8, MCT10, and OATPs, and the effects of genetic variation in these transporters. J Mol Endocrinol, 44 (1): 1-11. [PMID:19541799]

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