SLC19A1
Description
The SLC19A1 (solute carrier family 19 member 1) is a protein-coding gene located on chromosome 21.
Folate transporter 1 is a protein which in humans is encoded by the SLC19A1 gene. Transport of folate compounds into mammalian cells can occur via receptor-mediated (see folate receptor 1) or carrier-mediated mechanisms. A functional coordination between these 2 mechanisms has been proposed to be the method of folate uptake in certain cell types. Methotrexate (MTX) is an antifolate chemotherapeutic agent that is actively transported by the carrier-mediated uptake system. RFC1 plays a role in maintaining intracellular concentrations of folate. SLC19A1 has also been shown to transport the immune second messenger 2'3'-cGAMP. Individuals carrying a specific polymorphism of SLC19A1 (c.80GG) have lower levels of folate. Other studies have also shown that individuals carrying the c.80AA polymorphism who are treated with methotrexate have higher levels of this anti-folate chemotherapeutic agent. Personalized dosing of the drug depending on the patient's genotype may therefore be required. Alternative names include: Reduced folate carrier 1, Intestinal folate carrier 1.
SLC19A1, also known as Reduced Folate Transporter 1 (RFC1), is a protein that acts as an antiporter, mediating the import of reduced folates and certain cyclic dinucleotides while simultaneously exporting organic anions. This process is driven by the concentration gradient of the organic anions, making RFC1 a secondary active transporter. RFC1 has a high affinity for N5-methyltetrahydrofolate, the primary circulating form of folate, and also transports the antifolate drug methotrexate. Notably, RFC1 also imports immunoreactive cyclic dinucleotides, such as cyclic GMP-AMP (2'-3'-cGAMP), an immune messenger triggered by DNA viruses in the cytosol. When phosphorylated to AICAR monophosphate, 5-amino-4-imidazolecarboxamide riboside (AICAR) can serve as an organic anion for RFC1's antiporter activity.
SLC19A1 is also known as CHMD, FOLT, IFC-1, IFC1, IMD114, MEGAF, REFC, RFC, RFC1, RFT-1, hRFC, hSLC19A1.
