Production and ligand-binding characteristics of the soluble form of murine erythropoietin receptor.
A recombinant soluble form (sEPO-R) of erythropoietin (EPO) receptor (EPO-R) was produced by Chinese hamster ovary cells and isolated in high yield with the EPO-fixed gel. Ligand binding assays were done using three methods; precipitation of sEPO-R radiolabeled EPO complex and competition of sEPO-R for the binding of radiolabeled EPO with the cellular EPO-R. The results showed a Kd of 17 nM which was much lower than those for cellular EPO-R. One N-glycosylation site exists in sEPO-R but the glycosylation did not affect the binding affinity to EPO. A complex with a molecular size that corresponded to a 1:1 complex of EPO and sEPO-R was detected.
Nagao
M
M
Department of Food Science and Technology, Faculty of Agriculture, Kyoto University, Japan.
Masuda
S
S
Abe
S
S
Ueda
M
M
Sasaki
R
R
D000818:Animals; D001483:Base Sequence; D016466:CHO Cells; D006224:Cricetinae; D004921:Erythropoietin / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D007438:Introns; D007700:Kinetics; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D016133:Polymerase Chain Reaction; D017467:Receptors, Erythropoietin / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D015183:Restriction Mapping; D014162:Transfection
D009838:Oligodeoxyribonucleotides; D017467:Receptors, Erythropoietin; D011994:Recombinant Proteins; D004921:Erythropoietin