Background |
The N-formyl peptide receptor (FPR) is a chemotactic G protein-coupled receptor (GPCR) that is found on the surface of phagocytic leukocytes, such as neutrophils and monocytes. The human FPR family comprises three members, FPR, FPRL1 (also designated lipoxin A4 receptor) and FPRL2, and each family member contains specific residues, which are responsible for determining its ligand specificity. FPR, a seven transmembrane-domain receptor, primarily binds the chemoattractant N-formyl-methionyl-leucyl-phenylalanine (fMLP), which activates several biological processes, including chemotaxis, transcriptional activation, and actin reorganization. FPR also mediates the inhibition of neutrophil migration through binding to specific peptide fragments of annexin I, which causes calcium transients and affects inflammatory responses. |