Site-Directed Mutagenesis of Soybean Using Engineered Nucleases

Soybean (Glycine max) is an ancient polyploid and major agricultural legume crop providing nutritional protein and oil that can be processed into a variety of feed and food products. Several genetic bottlenecks throughout its domestication and more recent intensive selection and breeding practices have greatly reduced the genetic variability of soybean germplasm. Current efforts to expand genetic tools for breeding and gene discovery include random mutagenesis and RNAi-based approaches. However, an ideal mutagenesis approach for a highly duplicated genome like soybean would allow for the simultaneous recovery of plants with single or multiple mutations in each member of a gene family of interest without disruption to the rest of the genetic background. Site-directed mutagenesis using zinc-finger (ZFNs) and TAL-effector nucleases (TALENs) provide an attractive method for producing this desired result. Engineered nucleases are a recently developed tool for targeted gene alteration, and their implementation in several model plants and animals suggests they could potentially be of great utility to the soybean research community.