• Purity

  >95%, by SDS-PAGE under reducing conditions and visualized by silver stain

• Endotoxin Level

  <0.01 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its binding ability in a functional ELISA. When Folic Acid-Bovine Serum Albumin was coated at 5 μg/mL (100 μL/well), the concentration of rhFOLR-2 that produces 50% of the optimal binding response was found to be approximately 0.2 -1 nM.

• Source

  Chinese Hamster Ovary cell line, CHO-derived Gln22-His228, with a C-terminal 6-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  No results obtained: Gln22 predicted

• Predicted Molecular Mass

  25.4 kDa

• SDS-PAGE

  25-40 kDa, reducing conditions

Background: FOLR2

Folate Receptor 2 (FOLR2), also known as Folate Receptor beta, is a 38 kDa protein that mediates the cellular uptake of 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 (1, 2). Mature FOLR2 is an N-glycosylated protein that is anchored to the cell surface by a GPI linkage (3, 4). Human FOLR2 shares 83% amino acid sequence identity with mouse and rat FOLR2. FOLR2 is predominantly expressed in placenta, cells of the neutrophilic lineage, and some CD34+ hematopoietic progenitor cells (4 - 6). It is upregulated on myeloid  leukemias, head and neck squamous cell carcinomas, and several nonepithelial cancers (3, 5, 7). It is also upregulated on macrophages and monocytes at chronic inflammatory sites including rheumatoid arthritis synovium and glioblastoma (8 - 10). FOLR2 knockout mice do not show gross morphological defects, but they exhibit increased sensitivity to arsenate-induced teratogenicity (11, 12).

• References:

1. Fowler, B. et al. (2001) Kidney Int. 59:S-221.

2. Kelemen, L.E. (2006) Int. J. Cancer 119:243.

3. Shen, F. et al. (1994) Biochemistry 33:1209.

4. Ratnam, M. et al. (1989) Biochemistry 28:8249.

5. Ross, J.F. et al. (1999) Cancer 85:348.

6. Reddy, J.A. et al. (1999) Blood 93:3940.

7. Ross, J.F. et al. (1994) Cancer 73:2432.

8. Nakashima-Matsushita, N. et al. (1999) Arthritis Rheum. 42:1609.

9. van der Heijden, J.W. et al. (2009) Arthritis Rheum. 60:12.

10. Nagai, T. et al. (2009) Cancer Immunol. Immunother. Feb 24 epub.

11. Piedrahita, J.A. et al. (1999) Nat. Genet. 23:228.

12. Wlodarczyk, B. et al. (2001) Toxicol. Appl. Pharmacol. 177:238.

• Long Name:

  Folate Receptor 2

• Entrez Gene IDs:

  2350 (Human); 14276 (Mouse); 293154 (Rat)

• Alternate Names:

  beta-HFR; FBP; FBP/PL-1; folate receptor 2 (fetal); Folate receptor 2; folate receptor beta; folate receptor, beta; Folate receptor, fetal/placental; folate-binding protein, fetal/placental; FOLR2; FR-beta; FR-P3; Placental folate-binding protein