| 摘要 |
Provided is a DNA molecule comprising a multicistronic transcription unit coding for i) a selectable marker polypeptide functional in a eukaryotic host cell, and for ii) a polypeptide of interest, the polypeptide of interest having a translation initiation sequence separate from that of the selectable marker polypeptide, wherein the coding sequence for the polypeptide of interest is downstream from the coding sequence for the selectable marker in the multicistronic transcription unit, and the nucleic acid sequence coding for the selectable marker polypeptide comprises a mutation that decreases the translation efficiency of the selectable marker in a eukaryotic host cell. Also provided are methods for obtaining host cells expressing a polypeptide of interest, the host cells comprising the described DNA molecules. Further provided is the production of polypeptides of interest, comprising culturing host cells comprising the DNA molecules hereof. |
