RNAi: Prokaryotes Get in on the Act


The small CRISPR-derived RNAs of bacteria and archaea provide adaptive immunity by targeting the DNA of invading viruses and plasmids. Hale et al. (2009) now report on a new variant CRISPR/Cas complex in the archaeon Pyrococcus furiosus that uses guide RNAs to specifically target and cleave RNA not DNA. 
DOI: 10.1016/j.cell.2009.11.018