CHO cell lines are a workhorse for the production of pharmaceutical
proteins, but show some limitations in the variability and stability of
N-glycosylation profiles. One promising approach to addressing this at
the required systems-level is miRNA, which can regulate a large number
of genes and have predictable targets. Herein, we first identified de
novo 656 potential miRNAs in the CHO genome based on a combination of
literature, database searching, and miRNA sequencing. We further
sequenced mRNA from the same cultures, and used a combination of
mRNA-miRNA correlation analysis, target prediction and literature
searches to find miRNAs potentially targeting N-glycosylation. Our ten
best miRNA candidates were subjected to miRNA overexpression, knockdown,
or knock-out in CHO cell lines. Out of the ten candidates, four
(miR-128, miR-34c, miR-30b, and miR-449a) showed positive effects on
N-glycosylation and could be applied directly for CHO cell engineering.
The fact that 40% of the screened targets had a desired effect, and the
prediction of 656 miRNAs illustrates the massive potential of miRNA
engineering in CHO.