Figure 1.

Orthogonal gene regulation by CRISPRa and CRISPRi

Simultaneous CRISPRa and CRISPRi is possible using Cas orthologous, e.g., SpCas9 and SaCas9, since the sgRNAs do not complex with orthologous Cas enzymes. In this example, dSpCas9 is fused to a transcriptional activation domain (Act.) and dSaCas9 is fused to a transcriptional inhibitor (Inh.). Combined delivery of all components in the same cells can lead to upregulation of target gene 1 and downregulation of gene 2.