An angiogenin-binding protein from endothelial cells.
A 42-kDa bovine protein that binds bovine angiogenin [angiogenin binding protein (AngBP)] has been identified as a dissociable cell-surface component of calf pulmonary artery endothelial cells and a transformed bovine endothelial cell line, GM7373. Binding of 125I-labeled bovine angiogenin (125I-Ang) to AngBP occurs with an apparent Kd approximately 5 x 10(-10) M and is specific, saturable, and inhibited by excess unlabeled angiogenin. 125I-Ang can be crosslinked efficiently to AngBP by a water-soluble carbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbo-diimide. Bovine ribonuclease A competes with the binding of 125I-Ang to AngBP, but lysozyme does not. Direct binding to AngBP of 125I-labeled bovine ribonuclease A is, however, much weaker than that of 125I-Ang. Two enzymatically active derivatives of angiogenin cleaved at residues 60-61 and 67-68, respectively, fail to induce angiogenesis and also bind to AngBP only weakly. AngBP has been isolated by treatment of cells with heparan sulfate, affinity chromatography on angiogenin-Sepharose of the material dissociated from the cell surface, and gel filtration HPLC. The results suggest that AngBP has the characteristics of a receptor that may likely function in angiogenesis.
Hu
G F
GF
Center for Biochemical and Biophysical Sciences and Medicine, Harvard Medical School, Boston, MA 02115.
Chang
S I
SI
Riordan
J F
JF
Vallee
B L
BL
D043925:Angiogenesis Inducing Agents / Q000378:metabolism; D000818:Animals; D001665:Binding Sites; D002352:Carrier Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D002417:Cattle; D002460:Cell Line; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D004730:Endothelium, Vascular / Q000378:metabolism*; D007700:Kinetics; D008970:Molecular Weight; D016297:Mutagenesis, Site-Directed; D011506:Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D012259:Ribonuclease, Pancreatic
D043925:Angiogenesis Inducing Agents; D002352:Carrier Proteins; D011506:Proteins; C046366:angiogenin; D012259:Ribonuclease, Pancreatic