C1q Receptor, gamma (gC1qR, C1qBP, Complement Component 1, Q Subcomponent-binding Protein)

This monoclonal antibody recognizes a cell membrane C1q binding molecule that recognizes the globular heads of C1q. It is also present in plasma and the extracellular matrix. The molecule is an unusually acidic, single chain protein with an apparent molecular weight of 33kD. It does not possess a conventional sequence motif compatible with a membrane spanning segment nor a consensus site for a GPI anchor. gC1qR migrates as a single chain under both reducing and non-reducing conditions, but it behaves as an oligomer on gel-filtration in non-dissociating conditions. Its multimer formation may be a critical process by which the gC1qR molecule increases its affinity for multivalent ligands such as C1q. gC1qR has been shown to inhibit complement activation by preventing the binding of C1q to antibodies, suggesting that the binding site for gC1qR and the binding site for immune complexes, which are present on the C1q globular 'heads', may be located at the same position. gC1qR is capable of interacting with several proteins involved in blood clotting, namely, thrombin, prothrombin, the heparinbinding form of vitronectin, the ternary complex, vitronectin-thrombin-antithrombin, as well as high-molecular-weight kininogen and Hageman factor. Besides its role in the complement pathway, gC1qR participates in enhancement of Fc-receptor and CR1-mediated phagocytosis, procoagulant activity on platelets, and chemotactic activity on mast cells, eosinophils, neutrophils, and fibroblasts. gC1qR is expressed on a wide variety of cells and can serve as a binding site for plasma and microbial proteins. Its antigenic sites may be cryptic on cells in suspension but become exposed when the cells are fixed by bifunctional cross-linkers. Probably it is also expressed on the cell membrane as a tetramer. Crosslinking or activation may thus bring about a tetrameric assembly of gC1qR followed by a conformational change within the molecule, thereby exposing epitopes which are otherwise hidden. A form of gC1qR is also found inside the cell. Intracellular gC1qR has been shown to bind the cytoplasmic tail of the a1B-adrenergic receptor and to PKCu.\n\nApplications:\nSuitable for use in Western Blot, Flow Cytometry, Functional Studies, ELISA, Immunofluorescence and Immunoprecipitation. Other applications not tested.\n\nRecommended Dilution:\nFlow Cytometry: 1:50\nOptimal dilutions to be determined by the researcher.\n\nStorage and Stability:\nMay be stored at 4 degrees C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20 degrees C. Aliquots are stable for at least 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.

Prices direct from United States Biological

Quick response times

Exclusive Biosave savings/discounts

SPECIFICATIONS

Catalog Number

C0010-12C

Size

100ug

Applications

ELISA, FC, IF, IP, WB

Hosts

Mouse

Reactivities

Hum, Rat

Form

Supplied as a liquid in PBS, 0.1% BSA.

P Type

Mab

Purity

Purified by Protein G affinity chromatography.

Isotype

IgG1

References

1. Ghebrehiwet, B et al; Identification of functional domains on gC1Q-R, a cell surface protein that binds to the globular \"heads\" of C1Q, using monoclonal antibodies and synthetic peptides. Hybridoma 1996, 5: 333. 2. Ghebrehiwet, B et al; gC1q-R/p33, a member of a new class of multifunctional and multicompartmental cellular proteins, is involved in inflammation and infection. Immunol Rev 2001, 180: 65. 3. Peerschke, E et al; gC1qR/p33 blockade reduces Staphylococcus aureus colonization of target tissues in an animal model of infective endocarditis. Infect Immun 2006, 74: 4418. 4. Sansonno, D et al; Role of the receptor for the globular domain of C1q protein in the pathogenesis of hepatitis C virau-related cryoglobulin vascular damage. J Immunol 2009, 183: 6013.

Additional Info

Recognizes epitopes in the XC15 peptide that contains a binding site for high-molecular-weight kininogen and Factor XII. This clone recognizes both the mature (aa74-282) and truncated form, lacking residues 74-95. Species Crossreactivity: rat.