title: Expression of erythroid differentiation factor (EDF) in Chinese hamster ovary cells.
abstract: Plasmid DNA containing EDF subunit cDNA and mouse dihydrofolate reductase (DHFR) cDNA was transfected into CHO DHFR- cells by the calcium-phosphate method. DHFR positive transformants secreted recombinant EDF (r-EDF) constitutively in an active form and accumulated it in the conditioned medium. Furthermore, cells which were resistant to methotrexate (MTX : 0.5 microM) secreted r-EDF up to 1 microgram/ml. r-EDF was identical to natural EDF (n-EDF) produced by human acute monocytic leukemia cell line, THP-1, as regards its dimeric structure and a biological activity.
authors.affiliation: Central Research Labortories, Ajinomoto Co., Inc., Kawasaki, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Murata
authors.forename: K
authors.initials: K
authors.lastname: Onomichi
authors.forename: Y
authors.initials: Y
authors.lastname: Eto
authors.forename: H
authors.initials: H
authors.lastname: Shibai
authors.forename: M
authors.initials: M
authors.lastname: Muramatsu
mesh_terms: D028341:Activins; D000595:Amino Acid Sequence; D000818:Animals; D002454:Cell Differentiation; D002460:Cell Line; D003470:Culture Media; D004247:DNA / Q000235:genetics; D004351:Drug Resistance; D004591:Electrophoresis, Polyacrylamide Gel; D007118:Immunoassay; D007265:Inhibins / Q000096:biosynthesis* / Q000235:genetics; D008727:Methotrexate / Q000494:pharmacology; D010957:Plasmids; D011994:Recombinant Proteins / Q000096:biosynthesis; D013762:Tetrahydrofolate Dehydrogenase / Q000378:metabolism; D014162:Transfection
chemical_list: D003470:Culture Media; D011994:Recombinant Proteins; D028341:Activins; D007265:Inhibins; D004247:DNA; D013762:Tetrahydrofolate Dehydrogenase; D008727:Methotrexate