This post was updated on Dec 5, 2017.
In 2015, Zetsche et al. added to the CRISPR toolbox with their characterization of two Cpf1 orthologs that display cleavage activity in mammalian cells. Like Cas9 nucleases, Cpf1 family members contain a RuvC-like endonuclease domain, but they lack Cas9’s second HNH endonuclease domain. Cpf1 cleaves DNA in a staggered pattern and requires only one RNA rather than the two (tracrRNA and crRNA) needed by Cas9 for cleavage. In certain cases, Cpf1 may be better suited for genome editing than Cas9 - read on to learn more about Cpf1 and check out our CRISPR guide for a refresher on CRISPR/Cas9.