The CRISPR–Cas9 gene-editing system snips DNA, but a newly characterized version targets RNA instead.
The CRISPR–Cas system is used by many bacteria to combat viruses. Feng Zhang of the Broad Institute of MIT and Harvard in Cambridge, Massachusetts, Eugene Koonin of the US National Institutes of Health in Bethesda, Maryland, and their colleagues mined this natural diversity for alternatives to the DNA-cutting Cas9 enzyme. They found that an enzyme called C2c2 from the bacterium Leptotrichia shahii can be programmed to cut specific, single-stranded RNA targets in another bacterium, Escherichia coli.
With further tweaks, the system could be used to attach fluorescent tags to RNA, direct RNA to specific compartments in the cell or otherwise chemically modify RNAs to study their function.
Science http://dx.doi.org/10.1126/science.aaf5573 (2016)