title: Overexpression of Soybean Isoflavone Reductase (GmIFR) Enhances Resistance to Phytophthora sojae in Soybean.
abstract: Isoflavone reductase (IFR) is an enzyme involved in the biosynthetic pathway of isoflavonoid phytoalexin in plants. IFRs are unique to the plant kingdom and are considered to have crucial roles in plant response to various biotic and abiotic environmental stresses. Here, we report the characterization of a novel member of the soybean isoflavone reductase gene family GmIFR. Overexpression of GmIFR transgenic soybean exhibited enhanced resistance to Phytophthora sojae. Following stress treatments, GmIFR was significantly induced by P. sojae, ethephon (ET), abscisic acid (placeCityABA), salicylic acid (SA). It is located in the cytoplasm when transiently expressed in soybean protoplasts. The daidzein levels reduced greatly for the seeds of transgenic plants, while the relative content of glyceollins in transgenic plants was significantly higher than that of non-transgenic plants. Furthermore, we found that the relative expression levels of reactive oxygen species (ROS) of transgenic soybean plants were significantly lower than those of non-transgenic plants after incubation with P. sojae, suggesting an important role of GmIFR might function as an antioxidant to reduce ROS in soybean. The enzyme activity assay suggested that GmIFR has isoflavone reductase activity.
authors.affiliation: Key Laboratory of Soybean Biology of Chinese Education Ministry, Soybean Research Institute, Northeast Agricultural University Harbin, China.
authors.forename: Qun
authors.initials: Q
authors.lastname: Cheng
authors.affiliation: Key Laboratory of Soybean Biology of Chinese Education Ministry, Soybean Research Institute, Northeast Agricultural University Harbin, China ; Jiamusi Branch Academy of Heilongjiang Academy of Agricultural Sciences Jiamusi, China.
authors.forename: Ninghui
authors.initials: N
authors.lastname: Li
authors.affiliation: Key Laboratory of Soybean Biology of Chinese Education Ministry, Soybean Research Institute, Northeast Agricultural University Harbin, China.
authors.forename: Lidong
authors.initials: L
authors.lastname: Dong
authors.affiliation: Key Laboratory of Soybean Biology of Chinese Education Ministry, Soybean Research Institute, Northeast Agricultural University Harbin, China.
authors.forename: Dayong
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Soybean Biology of Chinese Education Ministry, Soybean Research Institute, Northeast Agricultural University Harbin, China.
authors.forename: Sujie
authors.initials: S
authors.lastname: Fan
authors.affiliation: Key Laboratory of Soybean Biology of Chinese Education Ministry, Soybean Research Institute, Northeast Agricultural University Harbin, China.
authors.forename: Liangyu
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Soybean Biology of Chinese Education Ministry, Soybean Research Institute, Northeast Agricultural University Harbin, China ; Heilongjiang Academy of Land Reclamation Sciences Harbin, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Key Laboratory of Soybean Biology of Chinese Education Ministry, Soybean Research Institute, Northeast Agricultural University Harbin, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Xu
authors.affiliation: Key Laboratory of Soybean Biology of Chinese Education Ministry, Soybean Research Institute, Northeast Agricultural University Harbin, China.
authors.forename: Shuzhen
authors.initials: S
authors.lastname: Zhang
keywords: Glycine max; Phytophthora sojae; antioxidant properties; gene expression; isoflavone reductase; isoflavonoid