TALENs: Customizable Molecular DNA Scissors for Genome Engineering of Plants

Precise genome modification with engineered nucleases is a powerful tool for studying basic biology and applied biotechnology. Transcription activator-like effector nucleases (TALENs), consisting of an engineered specific (TALE) DNA binding domain and a Fok I cleavage domain, are newly developed versatile reagents for genome engineering in different organisms. Because of the simplicity of the DNA recognition code and their modular assembly, TALENs can act as customizable molecular DNA scissors inducing double-strand breaks (DSBs) at given genomic location. Thus, they provide a valuable approach to targeted genome modifications such as mutations, insertions, replacements or chromosome rearrangements. In this article, we review the development of TALENs, and summarize the principles and tools for TALEN-mediated gene targeting in plant cells, as well as current and potential strategies for use in plant research and crop improvement.