摘要 |
The disclosure pertains to an expression vector or a combination of at least two expression vectors comprising: a) a polynucleotide encoding a mutated folate receptor as selectable marker, wherein the mutated folate receptor has a decreased folate binding affinity compared to the wild type folate receptor; b) at least one polynucleotide encoding a polypeptide of interest, wherein when said expression vector or combination of at least two expression vectors is introduced into a host cell, the polypeptide of interest is secreted from said host cell. Also provided are suitable host cells, selection methods and methods for producing polypeptides with high yield. |