Frizzled-4 Antibody (145901) [Alexa Fluor™ Plus 555]

• Reactivity: Hu, Mu
• Clone: 145901
• Clonality: Monoclonal
• Host: Rat
• Conjugate: Alexa Fluor Plus 555

Frizzled-4 Antibody (145901) [Alexa Fluor™ Plus 555] Summary

• Specificity: Detects human and mouse Frizzled-4 in Western blots. In Western blots, no cross-reactivity with recombinant mouse (rm) Frizzled-1, -2, -3, -6, -7, -8, or recombinant human Frizzled-5 is observed. Detects Frizzled-4 by flow cytometry and immunohistochemistry on mouse differentiated embryoid bodies derived from the mouse embryonic cell line, D3.
• Isotype: IgG2a
• Clonality: Monoclonal
• Host: Rat

Packaging, Storage & Formulations

• Storage: Protect from light. Do not freeze. 12 months from date of receipt, 2 to 8 °C as supplied
• Buffer: Supplied 0.2 mg/mL in a saline solution containing BSA and Sodium Azide.

Notes

This product is produced by and ships from R&D Systems, Inc., a Bio-Techne brand.

Alternate Names for Frizzled-4 Antibody (145901) [Alexa Fluor™ Plus 555]

• CD344 antigen
• CD344
• EVR1
• exudative vitreoretinopathy 1
• FEVR
• frizzled (Drosophila) homolog 4
• frizzled homolog 4 (Drosophila)
• Frizzled4
• Frizzled-4
• Fz-4
• FZD4
• FZD4S
• FzE4
• GPCR
• hFz4
• MGC34390
• WNT receptor frizzled-4

Background

Frizzled-4, designated CD344, is a 7-transmembrane glycoprotein of the Frizzled family within the G-protein coupled receptor superfamily (1, 2). Frizzled proteins function as receptors for Wnt proteins and can activate canonical Wnt/beta-catenin signaling as well as planar cell polarity and calcium flux pathways (1). Frizzled-4 is particularly important in angiogenic Wnt pathway signaling (1, 5). Frizzleds contain a divergent N-terminal signal peptide, a highly conserved ~120  amino acid (aa) cysteine-rich domain (CRD), a variable length linker region, seven transmembrane domains, and a variable-length C-terminal tail (1). The mouse Frizzled-4 cDNA encodes 537 aa with a 36 aa signal sequence and a 186 aa N-terminal extracellular sequence (4). The portion expressed includes aa 37-180, and shares 93%, 94%, 90%, 89% and 88% identity with human, rat, equine, bovine and canine Frizzled-4, respectively. This portion competes for Wnt binding with endogenous receptors. In humans, a 122 aa soluble form that diverges at aa 95 is proposed to be a positive regulator of Wnt signaling pathways (5). Frizzled-4 is unusual in binding a non-wnt ligand, Norrin, in addition to binding Wnt ligands (1, 3, 6). Norrin binds the Frizzled-4 CRD, activates Wnt signaling pathways and uses LRP5/6 as co-receptors (3, 6). Deletion of either Frizzled-4 or Norrin in mice results in a similar phenotype including malformation of vasculature in the retina, cerebellar degeneration, and loss of hair cells in the inner ear (1, 3, 7). In humans, blindness due to familial exudative vitreoretinopathy (FEVR) is associated with mutations producing loss of function of Frizzled-4 or Norrin, designated EVR1 and EVR2, respectively (1, 3, 8). Frizzled-4 expression has been found in many tissues, including mouse ovary, where it influences corpus luteum vasculogenesis and is necessary for fertility (4, 9).

1. Huang, H-C. and P.S. Klein (2004) Genome Biol. 5:234.
2. Parmalee, N.L. and J. Kitajewski (2008) Curr. Drug Targets 9:558.
3. Xu, Q. et al. (2004) Cell 116:883.
4. Wang, Y. et al. (1996) J. Biol. Chem. 271:4468.
5. Sagara, N. et al. (2001) Biochem. Biophys. Res. Commun. 282:750.
6. Smallwood, P.M. et al. (2007) J. Biol. Chem. 282:4057.
7. Wang, Y. et al. (2001) J. Neurosci. 21:4761.
8. Robitaille, J. et al. (2002) Nat. Genet. 32:326.
9. Hsieh, M. et al. (2005) Biol. Reprod. 73:1135.

Limitations

This product is for research use only and is not approved for use in humans or in clinical diagnosis. Primary Antibodies are guaranteed for 1 year from date of receipt.