title: Identification of proton-coupled high-affinity human intestinal folate transporter mutated in human hereditary familial folate malabsorption.
abstract: The human folate transporter of the small intestine has been identified and characterized. It functions optimally at the low pH (6.0-6.2) characteristic of the microenvironment of the duodenal brush border membrane, where dietary folates are mainly absorbed. The transporter, named PCFT/HCP1, is a protein of approximately 50 kDa and functions as a reversible, electrogenic, proton-coupled high-affinity folate transporter (PCFT). It shows high specificity for folates and anti-folates. This protein was previously identified as an intestinal heme carrier protein HCP1. Patients suffering from hereditary familial folate malabsorption were found to be homozygous for a mutation of the PCFT/HCP1 gene due to loss of a particular exon coding for 28 amino acids.
authors.affiliation: Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California, USA. nutritionreviews@ilsi.org
authors.forename: George
authors.initials: G
authors.lastname: Wolf
mesh_terms: D000818:Animals; D001692:Biological Transport; D004594:Electrophysiology; D005492:Folic Acid / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007421:Intestine, Small / Q000378:metabolism*; D008286:Malabsorption Syndromes / Q000235:genetics*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D010375:Pedigree; D013379:Substrate Specificity
chemical_list: D026901:Membrane Transport Proteins; D005492:Folic Acid