摘要 |
An expression vector capable of expressing in a vertebrate host cell culture a desired protein and a secondary protein, which vector comprises a DNA sequence encoding for a desired protein and a DNA sequence encoding for a secondary protein wherein both said DNA sequences are operably linked to the same promoter sequence and separated by translational stop and start codons. …<??>The secondary sequence provides for a convenient screening marker, both for transformants in general, and for transformants showing high expression levels for the primary sequence, as well as serving as a control device whereby the expression of a desired polypeptide can be regulated, most frequently enhanced. |