title: The soybean R2R3 MYB transcription factor GmMYB100 negatively regulates plant flavonoid biosynthesis.
abstract: Soybean flavonoids, a group of important signaling molecules in plant-environment interaction, ubiquitously exist in soybean and are tightly regulated by many genes. Here we reported that GmMYB100, a gene encoding a R2R3 MYB transcription factor, is involved in soybean flavonoid biosynthesis. GmMYB100 is mainly expressed in flowers, leaves and immature embryo, and its level is decreased after pod ripening. Subcellular localization assay indicates that GmMYB100 is a nuclear protein. GmMYB100 has transactivation ability revealed by a yeast functional assay; whereas bioinformatic analysis suggests that GmMYB100 has a negative function in flavonoid biosynthesis. GmMYB100-overexpression represses the transcript levels of flavonoid-related genes in transgenic soybean hairy roots and Arabidopsis, and inhibits isoflavonoid (soybean) and flavonol (Arabidopsis) production in transgenic plants. Furthermore, the transcript levels of six flavonoid-related genes and flavonoid (isoflavonoid and flavone aglycones) accumulation are elevated in the GmMYB100-RNAi transgenic hairy roots. We also demonstrate that GmMYB100 protein depresses the promoter activities of soybean chalcone synthase and chalcone isomerase. These findings indicate that GmMYB100 is a negative regulator in soybean flavonoid biosynthesis pathway.
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China.
authors.forename: Junhui
authors.initials: J
authors.lastname: Yan
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China. wangbiao@sjtu.edu.cn.
authors.forename: Biao
authors.initials: B
authors.lastname: Wang
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China.
authors.forename: Yunpeng
authors.initials: Y
authors.lastname: Zhong
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China.
authors.forename: Luming
authors.initials: L
authors.lastname: Yao
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China.
authors.forename: Linjing
authors.initials: L
authors.lastname: Cheng
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China.
authors.forename: Tianlong
authors.initials: T
authors.lastname: Wu
mesh_terms: D000595:Amino Acid Sequence; D000872:Anthocyanins / Q000032:analysis / Q000096:biosynthesis; D017360:Arabidopsis / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D047309:Flavones / Q000032:analysis / Q000096:biosynthesis; D005419:Flavonoids / Q000032:analysis / Q000096:biosynthesis*; D044948:Flavonols / Q000032:analysis / Q000096:biosynthesis; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000235:genetics; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D013025:Glycine max / Q000235:genetics / Q000502:physiology*; D013347:Subcellular Fractions / Q000737:chemistry; D014026:Nicotiana / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*
chemical_list: D000872:Anthocyanins; D047309:Flavones; D005419:Flavonoids; D044948:Flavonols; D010940:Plant Proteins; D014157:Transcription Factors; C043562:flavone
keywords: Flavonoids; GmMYB100; MYB transcription factor; Repressor; Soybean