Folate receptor 1 (FOLR1), also known as folate receptor alpha, folate binding protein (FBP), FOLR, is a member of the folate receptor (FOLR) family. Members of this gene family have a high affinity for folate and several reduced folate derivatives, mediating the intracellular transport of 5-methyltetrahydrofolate. Mature FOLR1 is a N-glycosylated protein anchored to the cell surface by a GPI link. FOLR1 is primarily expressed on epithelial cells and significantly upregulated in many tumors.