Pairwise library screen systematically interrogates Staphylococcus aureus Cas9 specificity in human cells

Autor: Luis A. Barrera, Josh Tycko, Patrick D. Hsu, Jonathan S. Gootenberg, Ari E. Friedland, Christine D. Wilson, Xuebing Wu, Vic E. Myer, Omar O. Abudayyeh, Nicholas C. Huston
Jazyk: angličtina
Rok vydání: 2018
Předmět:
Zdroj: Nature Communications, Vol 9, Iss 1, Pp 1-7 (2018)
Nature Communications
Nature communications, vol 9, iss 1
ISSN: 2041-1723
Popis: Therapeutic genome editing with Staphylococcus aureus Cas9 (SaCas9) requires a rigorous understanding of its potential off-target activity in the human genome. Here we report a high-throughput screening approach to measure SaCas9 genome editing variation in human cells across a large repertoire of 88,692 single guide RNAs (sgRNAs) paired with matched or mismatched target sites in a synthetic cassette. We incorporate randomized barcodes that enable whitelisting of correctly synthesized molecules for further downstream analysis, in order to circumvent the limitation of oligonucleotide synthesis errors. We find SaCas9 sgRNAs with 21-mer or 22-mer spacer sequences are generally more active, although high efficiency 20-mer spacers are markedly less tolerant of mismatches. Using this dataset, we developed an SaCas9 specificity model that performs robustly in ranking off-target sites. The barcoded pairwise library screen enabled high-fidelity recovery of guide-target relationships, providing a scalable framework for the investigation of CRISPR enzyme properties and general nucleic acid interactions.
A rigorous understanding of off-target effects is necessary for SaCas9 to be used in therapeutic genome editing. Here the authors measure SaCas9 mismatch tolerance across a pairwise library screen of 88,000 guides and targets in human cells and develop a model which ranks off-target sites.
Databáze: OpenAIRE