Secreted Frizzled Related Proteins (sFRPs) are a family of secreted, soluble vertebrate glycoproteins which contain homology to the Wnt-binding domain of the Frizzled (Fz) family of transmembrane receptors. sFRPs are ~30-35kD in size and are comprised of 3 domains: a signal sequence; an N-terminal Fz cysteine-rich domain (CRD) with 10 conserved cysteines; and a C-terminal heparin-binding region with weak homology to Netrin. The Fz CRD mediates Wnt-binding and is present in all Fz and sFRP family members (1). sFRP-1, also known as secreted apoptosis-related protein 2 (SARP-2), FRP and FrzA, is expressed in the embryonic kidney, eye, brain, teeth, salivary gland and small intestine, most often at sites of epithelial-mesenchyme interaction (5). Expression in the adult animal is strong in the eye, kidney, and heart and also prevalent in the brain and lung (2,5). sFRP-1 was first characterized as a protein that enhances the sensitivity of cells to apoptotic stimuli (3) and as an antagonist of Wnt signaling in Xenopus embryos (4). It is also characterized as a tumor suppressor in breast (6) and cervical carcinomas (7). In contrast, sFRP-1 is expressed by the majority of malignant gliomas (8) and contributes to the development of uterine leiomyomas (9), suggesting that the role of sFRP-1 is dependent on cell context. sFRP-1 has diverse activities, from inducing angiogenesis (10) in a variety of in vivo models to helping regulate Wnt-4 signaling (with sFRP-2) in renal organogenesis (11). Mouse and human sFRP-1 proteins share 94% amino acid identity (1).
Source:A DNA sequence encoding amino acid residues Met1-Lys313 of human secreted FrizzledRelated Protein-1 (hsFRP-1) (Melkonyan, H.S. et al., 1997, Proc. Natl. Acad. Sci. USA 94: 13636-13641) was expressed with a C-terminal His tag in a mouse myeloma cell line, NS0.
Molecular Mass:Mature recombinant human sFRP-1 is a monomeric protein. Based on N-terminal sequencing, three peptides, Ser31, Asp41 and Phe38 at their N-termini are present in this recombinant preparation in approximately equimolar amounts. As a result of glycosylation, the recombinant preparation migrates at ~35-40kD in SDS-PAGE under reducing conditions.
Biological Activity:Measured by its ability to inhibit proliferation of human HeLa cervical adenicarcinoma cells. The ED50 for this effect is typically 2.5-10ug/ml.
In an alternative assay, this protein also inhibits rmWnt-3A induced activation of beta-catenin reporter TOPFLASH in HEK293T cells.
Storage and Stability:Lyophilized powder may be stored at -20°C. Reconstitute to nominal volume by adding sterile PBS containing at least 0.1% HSA or BSA . Aliquot and store at -20°C. Reconstituted product is stable for 6 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
仕様
Size：25ug
Source Antigen：Recombinant, NS0 cells
Grade：Highly Purified
Purity：≥ 95%, as determined by SDS-PAGE and visualized by silver stain. Endotoxin:≤1EU/ug (LAL).
Form：Supplied as a lyophilized powder in PBS, pH 7.0, 50ug BSA/ug. Reconstitute with sterile PBS containing at least 0.1% HSA or BSA.
