Heidaran M A, Pierce J H, Jensen R A, Matsui T, Aaronson S A
Laboratory of Cellular and Molecular Biology, National Cancer Institute, Bethesda, Maryland 20892.
J Biol Chem. 1990 Nov 5;265(31):18741-4.
Binding of platelet-derived growth factor (PDGF) to its cell surface receptors stimulates a variety of biochemical and biological responses. Two receptor gene products (designated alpha and beta) have been identified, and the different binding affinities of various PDGF isoforms for these receptors are prime determinants of the spectrum of responses observed. The beta receptor binds PDGF-BB, but not PDGF-AA, while the alpha receptor binds PDGF-AA and PDGF-BB. We utilized these different ligand binding specificities to investigate the PDGF-AA binding site in the human alpha-PDGF receptor by constructing chimeric molecules between the human alpha- and beta-PDGF receptors. Our results demonstrate that amino acids 1-340 of the alpha-PDGF receptor comprise the region that confers PDGF-AA binding specificity. This region corresponds to immunoglobulin-like sub-domains 1, 2, and 3 of its external domain.
血小板衍生生长因子（PDGF）与其细胞表面受体的结合会刺激多种生化和生物学反应。已鉴定出两种受体基因产物（命名为α和β），各种PDGF异构体对这些受体的不同结合亲和力是观察到的反应谱的主要决定因素。β受体结合PDGF-BB，但不结合PDGF-AA，而α受体结合PDGF-AA和PDGF-BB。我们利用这些不同的配体结合特异性，通过构建人α-PDGF受体和β-PDGF受体之间的嵌合分子，研究人α-PDGF受体中的PDGF-AA结合位点。我们的结果表明，α-PDGF受体的氨基酸1-340构成赋予PDGF-AA结合特异性的区域。该区域对应于其胞外域的免疫球蛋白样亚结构域1、2和3。
