  Zinc-finger nucleases (ZFNs) and transcription activator-like effector
nucleases (TALENs) comprise a powerful class of tools that are redefining the
boundaries of biological research. Although these technologies have begun to
enable targeted genome modifications, there remains a need for new technologies
that are affordable, scalable, and easy to engineer. In this paper, we propose
a new tool for genetic engineering, the pseudocomplementary peptide nucleic
acid nucleases (pcPNANs), which are composed of a pseudocomplementary PNA
(pcPNA) specific for a DNA target sequence, a FokI nuclease cleavage domain and
a nuclear localization signal. pcPNANs may induce targeted DNA double-strand
breaks that activate DNA damage response pathways and enable custom
alterations. Their cleavage-site is determined by simple Watson-Crick rule, and
thus pcPNANs for aimed cleavage of genomes can be straightforwardly designed
and synthesized without any selection procedure. Accordingly, the cleavage-site
and site-specificity are freely chosen by changing the sequences and the
lengths of pcPNA strands. We believe that the potentiality of pcPNAN as a new
tool for genetic engineering will be confirmed in the future.
