Flavonoids,the largest class of polyphenols,exhibit substantial structural and functional diversity,yet their evolutionary diversification and specialized functions remain largely unexplored.The genus Scutellaria is n...Flavonoids,the largest class of polyphenols,exhibit substantial structural and functional diversity,yet their evolutionary diversification and specialized functions remain largely unexplored.The genus Scutellaria is notable for its rich flavonoid diversity,particularly of 6/8-hydroxylated variants biosynthesized by the cytochrome P450 subfamily CYP82D.Our study analyzes metabolic differences between Scutellaria baicalensis and Scutellaria barbata,and the results suggest that CYP82Ds have acquired a broad range of catalytic functions over their evolution.By integrating analyses of metabolic networks and gene evolution across 22 Scutellaria species,we rapidly identified 261 flavonoids and delineated five clades of CYP82Ds associated with various catalytic functions.This approach revealed a unique catalytic mode for 6/8-hydroxylation of flavanone substrates and the first instance of 7-O-demethylation of flavonoid substrates catalyzed by a cytochrome P450.Ancestral sequence reconstruction and functional validation demonstrated that gradual neofunctionalization of CYP82Ds has driven the chemical diversity of flavonoids in the genus Scutellaria throughout its evolutionary history.These findings enhance our understanding of flavonoid diversity,reveal the intricate roles of CYP82Ds in Scutellaria species,and highlight the extensive catalytic versatility of cytochrome P450 members within plant taxa.展开更多
Glycine max L.accumulates a large amount of isoflavonoid compounds,which is beneficial for plant defense,plant-microbe symbiotic interactions,and human health.Several CYP450 subfamily genes are involved in the flavono...Glycine max L.accumulates a large amount of isoflavonoid compounds,which is beneficial for plant defense,plant-microbe symbiotic interactions,and human health.Several CYP450 subfamily genes are involved in the flavonoid biosynthetic pathway in plants.In the present study,we found 24 CYP82 subfamily genes were differentially expressed in various tissues of soybean,in Phytophthora sojae-infected soybean varieties and in soybean hairy roots treated with cell wall glucan elicitor.Six of them(GmCYP82A2,GmCYP82A3,GmCYP82A4,GmCYP82A23,GmCYP82C20 and GmCYP82D26)were co-expressed with other known isoflavonoid pathway genes in soybean.Their enzymatic activity in yeast feeding assays showed that only GmCYP82D26 was able to convert naringenin to daidzein with both aryl migration and dehydration function.When GmCYP82D26 was over-expressed in soybean hairy roots,the contents of the two major isoflavonoid aglycones in soybean(daidzein and genistein)were reduced,but total flavonoids were not affected.When GmCYP82D26 was suppressed by RNAi in the hairy roots,daidzein content was decreased but genistein content was increased,with unchanged total flavonoid content.GmCYP82D26 was found to be localized in the endoplasmic reticulum at subcellular level when transiently expressed in tobacco leaf epidermis.GmCYP82D26 gene was preferentially expressed in roots,with low expression level in other tissues in soybean.Homology modeling and molecular docking showed that GmCYP82D26 could form hydrogen bond with both HEM and naringenin at C5-OH and C4 carbonyl.All these results indicated that GmCYP82D26 possesses new and dual enzymatic activity,which bridges the two branches(daidzein and genistein branch)of isoflavonoid pathway in soybean.展开更多
基金National Key Research and Development Program of China,grant 2023YFC3504800(to Y.X.)National Natural Science Foundation of China,grant 82470379(to S.Q.)+7 种基金Young Elite Scientists Sponsorship Program by Cast,grant 2021-QNRC1-02(to S.Q.)Organizational Key Research and Development Program of Shanghai University of Traditional Chinese Medicine,grant 2023YZZ02(to W.S.C.)The Open Fund of Shanghai Key Laboratory of Plant Functional Genomics and Resources,grant PFGR202501(to S.Q.)The National Natural Science Foundation of China,grant 82204577(to R.R.G.)The Research Project of Science and Technology Commission of Shanghai Municipality,grant 21DZ2202300(to S.Q.)Key project at the central government level:“The ability establishment of sustainable use for valuable Chinese medicine resources,”grant 2060302(to S.Q.)The Natural Science Foundation of Shanghai,grant 22ZR1479500(to Q.Z.)The China Postdoctoral Science Foundation,grant 2023M744290(to J.D.H.).
文摘Flavonoids,the largest class of polyphenols,exhibit substantial structural and functional diversity,yet their evolutionary diversification and specialized functions remain largely unexplored.The genus Scutellaria is notable for its rich flavonoid diversity,particularly of 6/8-hydroxylated variants biosynthesized by the cytochrome P450 subfamily CYP82D.Our study analyzes metabolic differences between Scutellaria baicalensis and Scutellaria barbata,and the results suggest that CYP82Ds have acquired a broad range of catalytic functions over their evolution.By integrating analyses of metabolic networks and gene evolution across 22 Scutellaria species,we rapidly identified 261 flavonoids and delineated five clades of CYP82Ds associated with various catalytic functions.This approach revealed a unique catalytic mode for 6/8-hydroxylation of flavanone substrates and the first instance of 7-O-demethylation of flavonoid substrates catalyzed by a cytochrome P450.Ancestral sequence reconstruction and functional validation demonstrated that gradual neofunctionalization of CYP82Ds has driven the chemical diversity of flavonoids in the genus Scutellaria throughout its evolutionary history.These findings enhance our understanding of flavonoid diversity,reveal the intricate roles of CYP82Ds in Scutellaria species,and highlight the extensive catalytic versatility of cytochrome P450 members within plant taxa.
基金supported by the Agricultural Science and Technology Innovation Program (ASTIP-IAS10).
文摘Glycine max L.accumulates a large amount of isoflavonoid compounds,which is beneficial for plant defense,plant-microbe symbiotic interactions,and human health.Several CYP450 subfamily genes are involved in the flavonoid biosynthetic pathway in plants.In the present study,we found 24 CYP82 subfamily genes were differentially expressed in various tissues of soybean,in Phytophthora sojae-infected soybean varieties and in soybean hairy roots treated with cell wall glucan elicitor.Six of them(GmCYP82A2,GmCYP82A3,GmCYP82A4,GmCYP82A23,GmCYP82C20 and GmCYP82D26)were co-expressed with other known isoflavonoid pathway genes in soybean.Their enzymatic activity in yeast feeding assays showed that only GmCYP82D26 was able to convert naringenin to daidzein with both aryl migration and dehydration function.When GmCYP82D26 was over-expressed in soybean hairy roots,the contents of the two major isoflavonoid aglycones in soybean(daidzein and genistein)were reduced,but total flavonoids were not affected.When GmCYP82D26 was suppressed by RNAi in the hairy roots,daidzein content was decreased but genistein content was increased,with unchanged total flavonoid content.GmCYP82D26 was found to be localized in the endoplasmic reticulum at subcellular level when transiently expressed in tobacco leaf epidermis.GmCYP82D26 gene was preferentially expressed in roots,with low expression level in other tissues in soybean.Homology modeling and molecular docking showed that GmCYP82D26 could form hydrogen bond with both HEM and naringenin at C5-OH and C4 carbonyl.All these results indicated that GmCYP82D26 possesses new and dual enzymatic activity,which bridges the two branches(daidzein and genistein branch)of isoflavonoid pathway in soybean.
