Abstract: PiggyBac transposases engineered to increase stability in a cell. The engineered piggyBac transposases are useful for stably transforming cells, cell line development, genome modification, and improving titer of recombinant proteins, among other uses.

Abstract: The present disclosure relates to the production of multimeric polypeptides (e.g., comprising two or more subunits, each subunit comprising two or more polypeptide chains, such as a multispecific or bispecific antibody) in eukaryotic host cells. In some embodiments, provided herein are methods for producing a multimeric polypeptide in a eukaryotic host cell using a host cell that comprises a polynucleotide comprising a translation initiation sequence operably linked to an open-reading frame encoding each polypeptide of the multimeric polypeptide. Advantageously, the present disclosure demonstrates that tuning the strength of the translation initiation sequences linked to each open-reading frame allows for higher production of the multimeric polypeptide with fewer incorrectly assembled side products. The present disclosure further provides cells, methods of screening, and kits related thereto.