TY  - JOUR
TI  - Gene targeting in plants: 25 years later
AU  - Puchta, Holger
AU  - Fauser, Friedrich
T2  - The International Journal of Developmental Biology
AB  - Only five years after the initiation of transgenic research in plants, gene targeting (GT) was achieved for the first time in tobacco. Unfortunately, the frequency of targeted integration via homologous recombination (HR) was so low in comparison to random integration that GT could not be established as a feasible technique in higher plants. It took another 25 years and great effort to develop the knowledge and tools necessary to overcome this challenge, at least for some plant species. In some cases, the overexpression of proteins involved in HR or the use of negative selectable markers improved GT to a certain extent. An effective solution to this problem was developed in 1996, when a sequence-specific endonuclease was used to induce a double-strand break (DSB) at the target locus. Thus, GT frequencies were enhanced dramatically. Thereafter, the main limitation was the absence of tools needed to induce DSBs at specific sites in the genome. Such tools became available with the development of zinc finger nucleases (ZFNs), and a breakthrough was achieved in 2005 when ZFNs were used to target a marker gene in tobacco. Subsequently, endogenous loci were targeted in maize, tobacco and Arabidopsis. Recently, our toolbox for genetic engineering has expanded with the addition of more types of site-specific endonucleases, meganucleases, transcription activator-like effector nucleases (TALENs) and the CRISPR/Cas system. We assume that targeted genome modifica-tions will become routine in the near future in crop plants using these nucleases along with the newly developed in planta GT technique.
PY  - 2013
DO  - 10.1387/ijdb.130194hp
VL  - 57
IS  - 6-7-8
SP  - 629
EP  - 637
J2  - Int. J. Dev. Biol.
LA  - en
SN  - 0214-6282
SN  - 1696-3547
UR  - https://ijdb.ehu.eus/article/130194hp
Y2  - 2024/11/05/15:25:07
ER  -