[Platelet-activating factor-from molecular biology to clinic].
Platelet-activating factor (PAF) is not only a potent proinflammatory compound, but is also involved in cell proliferation and differentiation. cDNAs coding for PAF receptors were isolated in our laboratory from human, guinea-pig, rat, and mouse. They consist of 341-342 amino acids with 7 putative transmembrane domains, characteristic of a G-protein-coupled-receptor superfamily. The gene for the human PAF receptor is located on chromosome 1, and has three separate exons. By 5'-alternative splicing, two transcripts (leukocyte- and heart-type) were expressed under the direction of two distinct promoters. Signal transduction of the PAF receptor disclosed that it couples with many effector systems including phospholipase C activation, inhibition of adenylate cyclase, MAP kinase activation, and phospholipase A2 activation. The multiplicify of these second messenger systems allows PAF to have a variety of biological activities, even though it is a single molecule and has no receptor subtypes.
Shimizu
T
T
Department of Biochemistry, Faculty of Medicine, University of Tokyo.
D000595:Amino Acid Sequence; D000818:Animals; D006168:Guinea Pigs; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D010972:Platelet Activating Factor / Q000737:chemistry / Q000502:physiology; D010980:Platelet Membrane Glycoproteins / Q000235:genetics; D051381:Rats; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D015290:Second Messenger Systems; D015398:Signal Transduction
D010972:Platelet Activating Factor; D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; C039351:platelet activating factor receptor