Solute carrier organic anion transporter family member 1C1 (SLCO1C1)

SLCO1C1, also known as Organic anion transporter 1C1 (OATP1C1), is a transmembrane protein belonging to the solute carrier family of organic anion transporters. It specifically facilitates sodium-independent, high-affinity transport of thyroid hormones such as L-thyroxine (T4), reverse triiodothyronine (rT3), and L-thyroxine sulfate (T4S) into brain tissues, especially astrocytes and glial cells. The transporter plays a crucial role in regulating the availability of thyroid hormones, which are essential for neuronal development and function. SLCO1C1 operates across the blood–brain barrier and is especially important for hormone signaling in the central nervous system. It exhibits 12 transmembrane domains and functions independently of sodium ions, with a transport mechanism similar to other major facilitator family proteins (“rocker-switch”). Genetic mutations in SLCO1C1 can cause severe CNS effects due to impaired hormone uptake and conversion, and altered expression can contribute to neurological and endocrine disease manifestations. Recently, SLCO1C1 is being investigated for its potential to facilitate targeted drug delivery to the brain, including as a vehicle for anti-inflammatory prodrugs in glial cells.

Other names

OATP1C1OATP-14OATP-FSLC21A14OATPFOAT-RP-5OATP-RP5Organic anion transporter 1C1Organic anion transporter FOrganic anion-transporting polypeptide 14Organic anion transporter polypeptide-related protein 5Thyroxine transporter

Sodium-independent high-affinity transport of specific organic anions (especially thyroid hormones) across cellular membranes; uptake into astrocytes and glia, enabling hormone conversion and CNS signaling