CRISPR activation (CRISPRa) allows researchers to up-regulate specific gene function by activating transcription, without editing the DNA. Visit our CRISPRa applications page to learn more.

The Horizon CRISPRmod CRISPRa system requires two components to operate: a CRISPRa guide RNA and a catalytically deactivated Cas9 (dCas9) fused to transcriptional activators (VPR). Our CRISPRa reagents provide a straightforward, efficient set of tools to study a gene’s function by overexpression in its native context. 


Algorithm-designed lentiviral and synthetic reagents specifically target promoter regions to induce a gene’s transcriptional activation.



Nuclease-deactivated Cas9, fused to three transcriptional activation domains.


SAM transcriptional activation system

  • SAM tracrRNA

    For use with synthetic CRISPRa crRNA and a stable cell line expressing both components (NLS-dCas9-VP64 and MS2-p65-HSF1) of the SAM activation system.

CRISPRa assay considerations for reagent selection

dCas9-VPR source Guide RNA format Delivery method Recommendations for use & benefits
CRISPRa dCas9-VPR lentiviral particle transduction & selection for dCas9-VPR stable cells CRISPRa synthetic crRNA Transfection or electroporation
  • Short timepoint assays (2-4 days)
  • Ability to pool crRNAs for increased target gene activation
  • Multiplex to activate >1 gene
  • Arrayed screening
CRISPRa lentiviral sgRNA particles Transduction
  • Extended timepoint assays with stable expression
  • Low MOI - single integration for stable and even activation in cell population
CRISPRa lentiviral sgRNA plasmid Transfection or electroporation
  • Short timepoint assays
  • Puromycin selection to enrich
  • Multiplex to activate >1 gene
CRISPRa dCas9-VPR lentiviral plasmid CRISPRa lentiviral sgRNA plasmid Co-transfection or electroporation with dCas9-VPR plasmid
  • Short timepoint assays
  • Antibiotics selection to enrich
  • No lentiviral integration
CRISPRa dCas9-VPR mRNA CRISPRa synthetic crRNA Co-transfection or electroporation
  • Short timepoint assays
  • Antibiotic and fluorescent options to enrich
  • No exogenous DNA, no integration of reagents in genome