A method for the recombinant production of a heterologous polypeptide in a eukaryotic host cell is described. The host cell comprises an expression plasmid, whereby the expression plasmid comprises in a 5′ to 3′ direction a) a promoter, b) a nucleic acid encoding a first polypeptide, whose amino acid sequence is selected from Table 1 depending on the first two amino acids of the second polypeptide, c) a nucleic acid encoding a second polypeptide comprising a nucleic acid encoding a heterologous polypeptide, a nucleic acid encoding a linker, and a nucleic acid encoding an immunoglobulin fragment, and d) a 3′ untranslated region comprising a polyadenylation signal. Further a plasmid and a kit are described.