title: Re-programming CHO cell metabolism using miR-23 tips the balance towards a highly productive phenotype.
abstract: microRNA engineering of CHO cells has already proved successful in enhancing various industrially relevant phenotypes and producing various recombinant products. A single miRNA's ability to interact with multiple mRNA targets allows their regulatory capacity to extend to processes such as cellular metabolism. Various metabolic states have previously been associated with particular CHO cell phenotypes such as glycolytic or oxidative metabolism accommodating growth and productivity, respectively. miR-23 has previously been demonstrated to play a role in glutamate metabolism resulting in enhanced oxidative phosphorylation through the TCA cycle. Re-programming cellular bioenergetics through miR-23 could tip the balance, forcing mammalian production cells to be more productive by favoring metabolic channelling into oxidative metabolism. CHO clones depleted of miR-23 using a miR-sponge decoy demonstrated an average ∼three-fold enhanced specific productivity with no impact on cell growth. Using a cell respirometer, mitochondrial activity was found to be enhanced by ∼30% at Complex I and II of the electron transport system. Additionally, label-free proteomic analysis uncovered various potential novel targets of miR-23 including LE1 and IDH1, both implicated in oxidative metabolism and mitochondrial activity. These results demonstrate miRNA-based engineering as a route to re-programming cellular metabolism resulting in increased productivity, without affecting growth.
authors.affiliation: National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland. paul.kelly@dcu.ie.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Kelly
authors.affiliation: National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland.
authors.forename: Laura
authors.initials: L
authors.lastname: Breen
authors.affiliation: National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland.
authors.forename: Clair
authors.initials: C
authors.lastname: Gallagher
authors.affiliation: National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland.
authors.forename: Shane
authors.initials: S
authors.lastname: Kelly
authors.affiliation: National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland.
authors.forename: Michael
authors.initials: M
authors.lastname: Henry
authors.affiliation: National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland.
authors.forename: Nga T
authors.initials: NT
authors.lastname: Lao
authors.affiliation: National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland.
authors.forename: Paula
authors.initials: P
authors.lastname: Meleady
authors.affiliation: Centre for Preventative Medicine, School of Health and Human Performance, Dublin City University, Dublin, Ireland.
authors.forename: Donal
authors.initials: D
authors.lastname: O'Gorman
authors.affiliation: National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland.
authors.forename: Martin
authors.initials: M
authors.lastname: Clynes
authors.affiliation: National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland.
authors.forename: Niall
authors.initials: N
authors.lastname: Barron
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D016466:CHO Cells; D060846:Cell Engineering; D049109:Cell Proliferation / Q000235:genetics; D006224:Cricetinae; D003412:Cricetulus; D018698:Glutamic Acid / Q000378:metabolism; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000235:genetics / Q000378:metabolism; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D040901:Proteomics; D020871:RNA Stability / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics
chemical_list: D035683:MicroRNAs; D012333:RNA, Messenger; D018698:Glutamic Acid; D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human; D000469:Alkaline Phosphatase
keywords: Chinese hamster ovary (CHO); Mitochondria; Productivity; miR-23; microRNA-sponge