C5a1 Receptor Phosphorylation Assays

C5a1 is the specific receptor for the chemotactic and inflammatory peptide anaphylatoxin C5a. Receptor activation stimulates chemotaxis, granule enzyme release, intracellular calcium release and superoxide anion production in macrophages and other immune cells. The development of potent and selective antagonists has been proposed as a strategy for new anti-inflammatory compounds for diseases in which damage by neutrophils plays a key role. C5a1 desensitization, β-arrestin recruitment and internalization is regulated by phosphorylation of carboxyl-terminal threonine324/serine327 (pT324/pS327-C5a1), serine332/serine334 (pS332/pS334-C5a1) threonine336 (pT336-C5a1), threonine338/threonine339 (pT338/pS339-C5a1) and threonine342 (pT342-C5a1) residues. This nomenclature refers to the human C5a1 receptor. This phosphorylation motif is conserved across species but corresponds to pS325/pS328-C5a1 and pS333/pS335-C5a1 in mice and pS325/pS328-C5a1 and pS334/pS336-C5a1 in rats. T324/S327 are also subject to phosphorylation by PKC. For more information on C5a1 receptor pharmacology please refer to the IUPHAR database. For further reading refer to:

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