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PAF receptor structure: a hypothesis.

J J Godfroid·G Dive·J Lamotte-Brasseur·J P Batt·F Heymans
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Abstract

Different hypotheses of the structure of platelet-activating factor (PAF) receptor based on structure-activity relationships of agonists and antagonists are reviewed. For an agonistic effect, strong hydrophobic interactions and an ether function are required in position-1 of the glycerol backbone; chain length limitations and steric hindrance demand a small group in position-2. The unusual structural properties of non-PAF-like antagonists required 3-D electrostatic potential calculations. This method applied to seven potent antagonists suggests a strong "Cache-orielles" (ear-muff) effect, i.e., two strong electronegative wells (isocontour at -10 Kcal/mole) are located at 180 degrees to each other and at a relatively constant distance. Initial consideration of the "Cache-oreilles" effect implied the structure of a bipolarized cylinder of 10-12 A diameter for the receptor. However, very recent results on studies with agonists and antagonists structurally similar to PAF suggest that the receptor may in fact be a multi-polarized cylinder.

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Models, MolecularMolecular ConformationPlatelet Activating FactorPlatelet Membrane GlycoproteinsProtein ConformationReceptors, Cell SurfaceReceptors, G-Protein-CoupledStructure-Activity RelationshipComparative StudyJournal ArticleReview

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BibTeXRIS

J J Godfroid, G Dive, J Lamotte-Brasseur, J P Batt, F Heymans. 1991. PAF receptor structure: a hypothesis.. https://doi.org/10.1007/bf02536523

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