Folate Receptor 3 (FOLR3), also known as folate receptor gamma, is a 32kD protein that binds folic acid and reduced folates. Dietary folates are required for many key metabolic processes including nucleotide and methionine synthesis, the interconversion of glycine and serine, and histidine breakdown. Mature FOLR3 is a glycosylated protein that contains an imperfect carboxy terminal GPI anchor sequence. A fraction of FOLR3 is GPI-linked to the cell surface, but the majority is released as a secreted protein. Mature human FOLR3 shares 74% and 83% aa sequence identity with FOLR1 and FOLR2, respectively. Orthologs of human FOLR3 have not been described in mouse or rat. A genetic polymorphism generates a truncated isoform that lacks the carboxy terminal 139aa. FOLR3 is expressed by cells of the myelocyte and B lymphocyte lineage as well as by various carcinomas. FOLR3 is more highly expressed in ovarian carcinomas than in breast carcinomas or mesotheliomas. Unlike other folate receptors, FOLR3 does not exhibit stereoselectivity in the binding of folates.
Source:Murine myeloma cell line, NS0-derived Ala22-Ser245 & Ser26-Ser245 both with a C-terminal 6-His tag (Accession # NP_000795)
SDS-PAGE:30-40kD, reducing conditions. Predicted MW is 26kD.
Biological Activity:Measured by its binding ability in a functional ELISA. When Folic Acid-BSA is coated at 5ug/ml (100ul/well), the concentration of rhFOLR-3 that produces 50% of the optimal binding response is found to be ~0.2-1nM.
Storage and Stability:Lyophilized and reconstituted products are stable for 6 months after receipt at -20°C. Reconstitute with sterile PBS. Aliquot to avoid repeated freezing and thawing. Store at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
