Betaine / Carnitine / Choline Transporters (BCCT) are a family of prokaryotic transport proteins that are specific for compounds containing a quaternary nitrogen atom. The BCCT proteins contain 12 transmembrane regions and are energized by sodiumsymport. They contain a conserved region with four tryptophans in their central region. All structures solved to date are trimeric.
The mammalian betaine transporter (SLC6A12) is regulated by NFAT5 during response to osmotic stress.
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