• Purity

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

• Endotoxin Level

  <0.10 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its binding ability in a functional ELISA. In a 100 µL reaction mixture containing biotinylated rmWnt-5a at 100 ng/mL and rhFrizzled-1/Fc Chimera dilutions at 0.1-8,000 ng/mL, the concentration of rhFrizzled-1/Fc Chimera that produces 50% of the optimal binding response is found to be approximately 20-80 ng/mL.    
     Optimal concentrations should be determined by each laboratory for each application.  

• Source

  Mouse myeloma cell line, NS0-derived

  Human Frizzled-1 (Gln73 - His253) Accession # Q9UP38	IEGRD	Human IgG1 (Pro100 - Lys330)
  N-terminus		C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Gly82 & No results obtained: Gln73 predicted

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  46.2 kDa (monomer)

• SDS-PAGE

  59-66 kDa, reducing conditions

Background: Frizzled-1

Frizzled-1 is one of at least ten seven-transmembrane (7TM) glycoproteins of the Frizzled family of Wnt receptors (1 - 3). Frizzled proteins are thought to be G-protein-coupled (1, 4). Wnt engagement, with low density lipoprotein receptor-related proteins LRP-5 or LRP-6 acting as co-receptors, stabilizes beta -catenin and promotes gene transcription that is important in development and tissue maintenance (1). Frizzled-1 can also act as a Wnt antagonist, for example, when sequestered from LRP-5/6 by LRP-1 (5, 6). Human Frizzled-1 cDNA encodes 647 aa including a 69 aa signal peptide, an extracellular cysteine-rich domain (CRD, aa 111 - 230) that binds Wnts and is highly conserved among Frizzleds, a linker region, the 7TM region, and the C-terminal cytoplasmic domain (2). Most Frizzleds, including Frizzled-1, contain a C-terminal PDZ binding motif (1). Within aa 73 - 253, human Frizzled-1 shares 94%, 93%, 97% and 98% aa identity with mouse, rat, bovine and canine Frizzled-1, respectively. Frizzleds can form homodimers or selective hetero-oligomers with other family members, which can involve the TM regions and possibly the CRD (1, 7). Frizzled-1 shares high aa identity (~76%) with Frizzled-2 and -7, but may differ in expression and Wnt selectivity (3, 8). Specifically, Wnt-3a interaction with rat Frizzled-1, but not Frizzled-2, blocks toxicity of the Alzheimers A beta peptide on PC12 cells (8). In bone, Frizzled-1 may be part of a feedback mechanism to modulate the effects of BMP-2 on mesenchymal cells (6, 9). Frizzled-1 is also one of the purported Wnt10b receptors whose signaling inhibits adipocyte differentiation (10). It is widely expressed, with mRNA detection in adult heart, placenta, lung, kidney, pancreas, prostate, and ovary, and in fetal lung and kidney (2).

• References:

1. Schulte, G. and B. Vitezslav (2007) Trends Pharmacol. Sci. 28:518.

2. Sagara, N. et al. (1998) Biochem. Biophys. Res. Commun. 252:117.

3. Gazit, A. et al. (1999) Oncogene 18:5959.

4. Liu, T. et al. (1999) J. Biol. Chem. 274:33539.

5. Zilberberg, A. et al. (2004) J. Biol. Chem. 279:17535.

6. Roman-Roman, S. et al. (2004) J. Biol. Chem. 279:5725.

7. Kaykas, A. et al. (2004) Nat. Cell Biol. 6:52.

8. Chacon, M.A. et al. (2008) J. Cell. Physiol. 217:215.

9. Yerges, L.M. et al. (2009) J. Bone Miner. Res. 24:87.

10. Bennett, C.N. et al. (2002) J. Biol. Chem. 277:30998.

• Entrez Gene IDs:

  8321 (Human); 14362 (Mouse)

• Alternate Names:

  DKFZp564G072; FLJ95923; frizzled family receptor 1; frizzled homolog 1; frizzled, Drosophila, homolog of, 1; Frizzled1; Frizzled-1; fz-1; FZD1; fzE1; hFz1; seven transmembrane spanning receptor; Wnt receptor