Although the CRISPR–Cas system of prokaryotes has an established role in defence, recent studies suggest that this system has other functional roles. Here, Westra and colleagues explore the more unconventional roles of CRISPR–Cas, such as endogenous gene regulation and genome remodelling, and consider their evolutionary implications.
- Edze R. Westra
- Angus Buckling
- Peter C. Fineran