Receptor for the chemotactic and inflammatory C3a, C4a and C5a anaphylatoxin peptides and also for their dearginated forms ASP/C3adesArg, C4adesArg and C5adesArg respectively. Couples weakly to G(i)-mediated signaling pathways. Interacts with C3 (the anaphylatoxin peptide C3a and the adipogenic hormone ASP); the interaction occurs with higher affinity for ASP, enhancing the phosphorylation and activation of GPR77, recruitment of ARRB2 to the cell surface and endocytosis of GRP77. Belongs to the G-protein coupled receptor 1 family.