C5a anaphylatoxin chemotactic receptor 1 (CD88/C5AR1) is a ~39 kDa protein. Receptor for the chemotactic and inflammatory peptide anaphylatoxin C5a, stimulating chemotaxis, granule enzyme release, intracellular calcium release and superoxide anion production. Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of downstream effectors, such as adenylate cyclase. C5AR1 is coupled to G(i)/G(o) (GNAI1 or GNAO1) G alpha proteins and mediates inhibition of adenylate cyclase. The ligand interacts with at least two sites on the receptor: a high-affinity site on the extracellular N-terminus, and a second site in the transmembrane region which activates downstream signaling events. 1. Christophe, T. et al. (2000) The Journal of biological chemistry 275, 1656-64. PMID: 106368592. Postma, B. et al. (2004) Journal of immunology (Baltimore, Md. : 1950) 172, 6994-7001. PMID: 151535206. Monk, PN. et al. (1995) The Journal of biological chemistry 270, 16625-9. PMID: 76224717. DeMartino, JA. et al. (1994) The Journal of biological chemistry 269, 14446-50. PMID: 81820498. Chen, Z. et al. (1998) The Journal of biological chemistry 273, 10411-9. PMID: 9553099 | 
