Targeted gene mutation in plants

Abstract

Recent advances in genome engineering provide plant biologists with an important tool for understanding gene function and developing new traits. Three powerful techniques, including zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and RNA-guided endonucleases (RGENs), have been developed for targeted DNA sequence modifications. These sequence-specific nucleases create double-strand breaks (DSBs) in the genomic target sites that are primarily repaired by the nonhomologous end-joining (NHEJ) or homologous recombination (HR) pathways, which can be employed to achieve targeted genome modifications such as gene mutations, insertions, replacements, or chromosome rearrangements. Considerable efforts have been made to understand the mechanisms governing gene targeting and establish an efficient DNA delivery system to achieve precise gene targeting in plants.