[The Efficiency of Gene Activation Using CRISPR/dCas9-Based Transactivation Systems Depends on the System Run Time]

Transactivation systems are a promising application based on the CRISPR/Cas9 system and allow targeted control of gene expression levels in cell culture. However, their performance has been reported to vary considerably depending on the cell type and the activator system. Three activator systems (dCas9-VP160, dCas9-SunTag, and dCas9-VPR) were compared for the efficiency of activating expression of OCT4, NANOG, PDX1, FOXA2, NKX2-2, and NKX6-1 in an immortalized human skin fibroblast line. The activation efficiency was found to depend on the activation system type; the extent of activation depended on the system run time.