CRISPR technologies and the search for the PAM-free nuclease.
review · Level V
Where this comes from
- Record sourced from PubMed, PMID 33483498.
- Also identified by DOI 10.1038/s41467-020-20633-y and PMC identifier 7822910.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The ever-expanding set of CRISPR technologies and their programmable RNA-guided nucleases exhibit remarkable flexibility in DNA targeting. However, this flexibility comes with an ever-present constraint: the requirement for a protospacer adjacent motif (PAM) flanking each target. While PAMs play an essential role in self/nonself discrimination by CRISPR-Cas immune systems, this constraint has launched a far-reaching expedition for nucleases with relaxed PAM requirements. Here, we review ongoing efforts toward realizing PAM-free nucleases through natural ortholog mining and protein engineering. We also address potential consequences of fully eliminating PAM recognition and instead propose an alternative nuclease repertoire covering all possible PAM sequences.
Medical subject headings
- CRISPR-Associated Protein 9
- CRISPR-Cas Systems
- Gene Editing
- Nucleotide Motifs
- RNA, Guide, CRISPR-Cas Systems