Differential expression of miRNAs and functional role of mir-200a in high and low productivity CHO cells expressing an Fc fusion protein

Objectives: We used miRNA and proteomic profiling to understand intracellular pathways that contribute to high and low specific productivity (Qp) phenotypes in CHO clonally derived cell lines (CDCLs) from the same cell line generation project. Results: Differentially expressed (DE) miRNAs were identified which are predicted to target several proteins associated with protein folding. MiR-200a was found to have a number of predicted targets associated with the unfolded protein response (UPR) which were shown to have decreased expression in high Qp CDCLs and have no detected change at the mRNA level. MiR-200a overexpression in a CHO CDCL was found to increase recombinant protein titer by 1.2 fold and Qp by 1.8 fold. Conclusion: These results may suggest a role for miR-200a in post-transcriptional regulation of the UPR, presenting miR-200a as a potential target for engineering industrially attractive CHO cell phenotypes.