Complementation of metabolic defect in phosphoglycerate kinase (PGK)-deficient line of Chinese hamster ovary cells by introduction of human PGK cDNA.

A full-length copy of the coding sequence of the human phosphoglycerate kinase (PGK) gene was introduced into a glycolysis-negative, PGK-deficient line of Chinese hamster ovary (CHO-K1) cells by gene transfer. Transformants were isolated either by cotransfer of the bacterial aminoglycoside phosphotransferase (AGPT) gene, or by direct selection for expression of the PGK gene. Integration of the human PGK gene has been demonstrated by Southern blot analysis and its expression by starch gel electrophoresis. PGK transformants behaved phenotypically as predicted by the properties of their wild type parent: mannose was no longer toxic, but instead was metabolized via glycolysis to lactic acid, and cell growth was no longer dependent on glutamine oxidation. Thus a complex phenotypic change has been mediated by gene transfer. The combination of R1.1.7 cells and the PGK plasmid provides another system to facilitate the study of mammalian gene expression.