Article Synopsis
- CRISPR/Cas9 is a powerful tool for editing genomes, reliant on the presence of a specific DNA sequence known as the Protospacer Adjacent Motif (PAM).
- Using this PAM requirement, researchers can selectively target single-nucleotide mutations in genes without affecting the normal versions of those genes.
- The study focuses on a specific mutation in the KRAS gene associated with colorectal cancer, demonstrating that targeting this mutation can overcome drug resistance in cancer treatment.
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Article Abstract
CRISPR/Cas9 is an enabling RNA-guided technology for genome targeting and engineering. An acute DNA binding constraint of the Cas9 protein is the Protospacer Adjacent Motif (PAM). Here we demonstrate that the PAM requirement can be exploited to specifically target single-nucleotide heterozygous mutations while exerting no aberrant effects on the wild-type alleles. Specifically, we target the heterozygous G13A activating mutation of KRAS in colorectal cancer cells and we show reversal of drug resistance to a MEK small-molecule inhibitor. Our study introduces a new paradigm in genome editing and therapeutic targeting via the use of gRNA to guide Cas9 to a desired protospacer adjacent motif.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4720446 | PMC |
| http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0144970 | PLOS |
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