Application note: CRISPR-Cas9 screening for target identification

The identification and validation of novel drug targets is a challenging process for drug discovery programmes.

Forward genetic screening with the RNA-guided nuclease Cas9 provides a new and powerful tool to interrogate gene function at a genome-wide level. In contrast to RNAi technology, which can be prone to off-target effects and variable knockdown efficiencies, the combination of bacterial CRISPR (clustered regularly interspaced short palindromic repeat)-associated Cas9 nuclease and pooled short guide RNA (sgRNA) libraries aims to generate complete knockouts with high on-target specificity. We have adapted a pooled-based screening protocol, where lentivirus transduction delivers both the Cas9 endonuclease and the sgRNA to the cells.