A CRISPR activation and interference toolkit for industrial Saccharomyces cerevisiae strain KE6-12.Recent advances in CRISPR/Cas9 based genome editing have considerably advanced genetic engineering of industrial yeast strains.  In this study, we report the construction and characterization of a toolkit for CRISPR activation and interference (CRISPRa/i) for a polyploid industrial yeast strain.  In the CRISPRa/i plasmids that are available in high and low copy variants, dCas9 is expressed alone, or as a fusion with an activation or repression domain; VP64, VPR or Mxi1.  The sgRNA is introduced to the CRISPRa/i plasmids from a double stranded oligonucleotide by in vivo homology-directed repair, allowing rapid transcriptional modulation of new target genes without cloning.  The CRISPRa/i toolkit was characterized by alteration of expression of fluorescent protein-encoding genes under two different promoters allowing expression alterations up to ~ 2.5-fold.  Furthermore, we demonstrated the usability of the CRISPRa/i toolkit by improving the tolerance towards wheat straw hydrolysate of our industrial production strain.  We anticipate that our CRISPRa/i toolkit can be widely used to assess novel targets for strain improvement and thus accelerate the design-build-test cycle for developing various industrial production strains.
CRISPR
A CRISPR activation and interference toolkit for industrial Saccharomyces cerevisiae strain KE6-12.Recent advances in CRISPR/Cas9 based genome editing have considerably advanced genetic engineering of industrial yeast strains. 
CRISPR/Cas9
In this study, we report the construction and characterization of a toolkit for CRISPR activation and interference (CRISPRa/i) for a polyploid industrial yeast strain.  In the CRISPRa/i plasmids that are available in high and low copy variants, dCas9 is expressed alone, or as a fusion with an activation or repression domain; VP64, VPR or Mxi1.  The sgRNA is introduced to the CRISPRa/i plasmids from a double stranded oligonucleotide by in vivo homology-directed repair, allowing rapid transcriptional modulation of new target genes without cloning.  The CRISPRa/i toolkit was characterized by alteration of expression of fluorescent protein-encoding genes under two different promoters allowing expression alterations up to ~ 2.5-fold.  Furthermore, we demonstrated the usability of the CRISPRa/i toolkit by improving the tolerance towards wheat straw hydrolysate of our industrial production strain.  We anticipate that our CRISPRa/i toolkit can be widely used to assess novel targets for strain improvement and thus accelerate the design-build-test cycle for developing various industrial production strains.
CRISPRa/i