platelet-activating factor receptor, member of the class A family of seven-transmembrane G protein-coupled receptors
The platelet-activating factor receptor is a G(q/11)-protein coupled receptor, which is linked to p38 MAPK and PI3K signaling pathways. PAF is a phospholipid (1-0-alkyl-2-acetyl-sn-glycero-3-phosphorylcholine) which is synthesized by cells especially involved in host defense such as platelets, macrophages, neutrophils, and monocytes. PAF is well-known for its ability to induce platelet aggregation and anaphylaxis, and also plays important roles in allergy, asthma, and inflammatory responses, among many others.
Comment:based on the structures of some class A family members with bound ligands (peptides or chemicals), agonists, or antagonists
Comment:Small-molecule chemical ligands tend to bind deeper within the receptor core, compared to a peptide ligand neurotensin, which binds towards the extracellular surface of its receptor.
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