Recombinant Human GPR56 Protein, CF

Recombinant Human GPR56 Protein, CF Summary

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: GPR56

GPR56 is a member of the LN-TM7 family of adhesion-type 7-transmembrane (TM) G-protein coupled receptors (GPCR) with long extracellularN-termini (1 - 3). The 693 amino acid (aa) human GPR56 contains a 25 aa signal sequence, a 377 aa N-terminal extracellular domain (ECD) and seven TM regions separated by short intracellular and extracellular regions. Like other LN-TM7 members, the ECD contains a highly glycosylated mucin-like stalk followed by a GPCR proteolytic cleavage site (GPS) (1, 4). Cleavage of the 60 kDa N-terminus from the 80 kDa full length form is needed for efficient cell surface expression (5, 6). While the cleaved portion may remain non-covalently associated, it has also been found in conditioned medium of cultured cells (5). Human GPR56 shares 71%, 72%, 80%, 80% and 79% aa identity with mouse, rat, canine, equine, and bovine GPR56 within the cleaved ECD. A functional splice variant lacking the GPS site and a non-functional splice variant lacking portions of the TM domains have also been described (4). A human brain developmental disorder, bilateral frontoparietal polymicrogyria, is associated with GPR56 mutations that also show impaired GPS cleavage, intracellular trafficking, and expression at the cell surface (5). GPR56 is widely distributed, with highest mRNA or expressed sequence tag expression in brain, thyroid, skin and female reproductive system (3, 4). GPR56 expression is upregulated during cell transformation and is high in melanomas, glioblastomas and astrocytomas, but downregulated in melanomas with high metastatic potential (2, 6 - 8). Although the function of GPR56 is not completely known, it is clearly an adhesion protein (6 - 8). Tissue transglutaminase (TG2) is one reported ligand, binding of which inhibits melanoma growth and metastasis (6). Association of GPR56 with the tetraspanin CD81 stabilizes its complex with Gaq/11 for cell signaling (9).

Related Research Areas

• Adhesion G Protein-Coupled Receptors
• G Protein-Coupled Receptors in Immune Responses