title: Targeted mutagenesis using zinc-finger nucleases in Arabidopsis.
abstract: Targeted mutagenesis is an essential tool of reverse genetics that could be used experimentally to investigate basic plant biology or modify crop plants for improvement of important agricultural traits. Although targeted mutagenesis is routine in several model organisms including yeast and mouse, efficient and widely usable methods to generate targeted modifications in plant genes are not currently available. In this study we investigated the efficacy of a targeted-mutagenesis approach based on zinc-finger nucleases (ZFNs). In this procedure, ZFNs are used to generate double-strand breaks at specific genomic sites, and subsequent repair produces mutations at the break site. To determine whether ZFNs can cleave and induce mutations at specific sites within higher plant genomes, we introduced a construct carrying both a ZFN gene, driven by a heat-shock promoter, and its target into the Arabidopsis genome. Induction of ZFN expression by heat shock during seedling development resulted in mutations at the ZFN recognition sequence at frequencies as high as 0.2 mutations per target. Of 106 ZFN-induced mutations characterized, 83 (78%) were simple deletions of 1-52 bp (median of 4 bp), 14 (13%) were simple insertions of 1-4 bp, and 9 (8%) were deletions accompanied by insertions. In 10% of induced individuals, mutants were present in the subsequent generation, thus demonstrating efficient transmission of the ZFN-induced mutations. These data indicate that ZFNs can form the basis of a highly efficient method for targeted mutagenesis of plant genes.
authors.affiliation: Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112-0840, USA.
authors.forename: Alan
authors.initials: A
authors.lastname: Lloyd
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Plaisier
authors.forename: Dana
authors.initials: D
authors.lastname: Carroll
authors.forename: Gary N
authors.initials: GN
authors.lastname: Drews
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development; D001483:Base Sequence; D004249:DNA Damage; D004252:DNA Mutational Analysis; D004260:DNA Repair; D003851:Deoxyribonucleases / Q000737:chemistry / Q000378:metabolism*; D018390:Gene Targeting / Q000379:methods*; D006358:Hot Temperature; D016296:Mutagenesis; D036226:Seedlings / Q000502:physiology; D016335:Zinc Fingers
chemical_list: D003851:Deoxyribonucleases