A deletion in the extracellular domain of the alpha platelet-derived growth factor (PDGF) receptor differentially impairs PDGF-AA and PDGF-BB binding affinities.
32D cells transfected with the human alpha platelet-derived growth factor receptor (alpha PDGFR) bind PDGF-AA, -AB, and -BB isoforms with high affinity, and the binding of each can be efficiently competed by all three isoforms. In an effort to develop better understanding of spatial relationships of binding sites for PDGF-AA and -BB, we constructed an alpha PDGFR mutant which deleted amino acids 150-189 within its extracellular domain. This mutant showed a marked decrease in high affinity binding sites for PDGF-AA without comparable alteration in affinity for PDGF-BB. These findings imply that the high affinity binding sites for PDGF-AA and PDGF-BB in the alpha PDGFR extracellular domain are not structurally coincident.
Heidaran
M A
MA
Laboratory of Cellular and Molecular Biology, National Cancer Institute, Bethesda, Maryland 20892.
Yu
J C
JC
Jensen
R A
RA
Pierce
J H
JH
Aaronson
S A
SA
D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D002872:Chromosome Deletion; D004261:DNA Replication / Q000187:drug effects; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis; D010982:Platelet-Derived Growth Factor / Q000378:metabolism* / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D011956:Receptors, Cell Surface / Q000235:genetics* / Q000378:metabolism*; D017479:Receptors, Platelet-Derived Growth Factor; D011994:Recombinant Proteins / Q000378:metabolism; D014162:Transfection
D009838:Oligodeoxyribonucleotides; D010982:Platelet-Derived Growth Factor; D011956:Receptors, Cell Surface; D011994:Recombinant Proteins; D017479:Receptors, Platelet-Derived Growth Factor