PAM multiplicity marks genomic target sites as inhibitory to CRISPR-Cas9 editing.
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ABSTRACT:
SUBMITTER: Malina A
PROVIDER: S-EPMC4686818 | biostudies-literature | 2015 Dec
REPOSITORIES: biostudies-literature
Publications
PAM multiplicity marks genomic target sites as inhibitory to CRISPR-Cas9 editing.
Malina Abba A Cameron Christopher J F CJF Robert Francis F Blanchette Mathieu M Dostie Josée J Pelletier Jerry J
Nature communications 20151208
In CRISPR-Cas9 genome editing, the underlying principles for selecting guide RNA (gRNA) sequences that would ensure for efficient target site modification remain poorly understood. Here we show that target sites harbouring multiple protospacer adjacent motifs (PAMs) are refractory to Cas9-mediated repair in situ. Thus we refine which substrates should be avoided in gRNA design, implicating PAM density as a novel sequence-specific feature that inhibits in vivo Cas9-driven DNA modification. ...[more]
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