Engineered highly specific endonucleases that can be used for gene targeting by introducing a double-strand break into a complex genome and thereby stimulating homologous recombination.

<p>With the exception of engineered homing endonucleases (“meganucleases”) in which the function of DNA binding and DNA cleavage is present in the same polypeptide chain [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082539#B77" target="_blank">77</a>], the other engineered nucleases consist of separate DNA-binding (green) and DNA-cleavage (blue) modules. Zinc finger nucleases and TALE nucleases usually have the non-specific cleavage domain of the restriction endonuclease FokI as DNA-cleavage module, but as shown recently and in the present paper the restriction endonuclease PvuII can also be used for this purpose [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082539#B54" target="_blank">54</a>]. PvuII has also been employed in TFO-linked nucleases [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082539#B49" target="_blank">49</a>] and in protein fusions (with catalytically inactive I-SceI) [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082539#B53" target="_blank">53</a>] as DNA-cleavage module. Zinc finger nucleases, TALE nucleases and TFO-linked nucleases are programmable, as are the RNA-mediated nucleases [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082539#B36" target="_blank">36</a>] [modified after [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082539#B3" target="_blank">3</a>]] .