High level of expression of the myelin protein P0 in Chinese hamster ovary cells.

The major PNS myelin protein, P0, has been expressed in Chinese hamster ovary cells by transfection with a plasmid containing the P0-cDNA. The expression of P0 at both the RNA and the protein level was greatly increased, without detriment to the cell, by the dihydrofolate reductase-methotrexate strategy of gene amplification. The P0 expressed by these cells was glycosylated (containing approximately equal amounts of the complex and high-mannose type glycoproteins) and reached the plasma membrane. This system is suitable not only for addressing the function of P0 directly, but it also applicable to any protein of which an abundance is needed.