PT - JOURNAL ARTICLE AU - David JHF Knapp AU - Yale S Michaels AU - Max Jamilly AU - Quentin RV Ferry AU - Hector Barbosa AU - Thomas A Milne AU - Tudor A Fulga TI - Decoupling tRNA promoter and processing activities enables specific Pol-II Cas9 guide RNA expression AID - 10.1101/342485 DP - 2018 Jan 01 TA - bioRxiv PG - 342485 4099 - http://biorxiv.org/content/early/2018/06/08/342485.short 4100 - http://biorxiv.org/content/early/2018/06/08/342485.full AB - Spatial/temporal control of Cas9 guide RNA expression could considerably expand the utility of CRISPR-based technologies. Current approaches based on tRNA processing offer a promising strategy but suffer from high background. Here we developed a variant screening platform to identify differential sequence determinants of human tRNA promoter and processing activities. Rational design based on the ensuing principles allowed us to engineer an improved tRNA scaffold that enabled highly specific guide RNA production from a Pol-II promoter.