Monocarboxylate transporters 8 and 10, and similar proteins of the Major Facilitator Superfamily of transporters
Monocarboxylate transporters 8 (MCT8) and 10 (MCT10) are transporters which stimulate the cellular uptake of thyroid hormones such as thyroxine (T4), triiodothyronine (T3), reverse triiodothyronine (rT3) and diidothyronine (T2). MCT has a preference for T3 and is also a sodium-independent transporter that mediates the uptake or efflux of aromatic acids such as Phe, Tyr, and Trp, as well as L-3,4-di-hydroxy-phenylalanine. MCT8/10 and similar proteins belong to the Monocarboxylate transporter (MCT) family of the Major Facilitator Superfamily (MFS) of membrane transport proteins. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.
Feature 1:putative chemical substrate binding pocket [chemical binding site]
Evidence:
Comment:based on the structures of MFS transporters with bound substrates, substrate analogs, and/or inhibitors
Comment:since MFS proteins facilitate the transport of many different substrates including ions, sugar phosphates, drugs, neurotransmitters, nucleosides, amino acids, and peptides, the residues involved in substrate binding may not be strictly conserved among superfamily members
Comment:the substrate binding site or translocation pore has access to both sides of the membrane in an alternating fashion through a conformational change of the MFS transporter
Jiyao W et al.(2023). "The conserved domain database in 2023.",