Panax notoginseng,a perennial herb of the genus Panax in the family Araliaceae,has played an important role in clinical treatment in China for thousands of years because of its extensive pharmacological effects.Here,w...Panax notoginseng,a perennial herb of the genus Panax in the family Araliaceae,has played an important role in clinical treatment in China for thousands of years because of its extensive pharmacological effects.Here,we report a high-quality reference genome of P.notoginseng,with a genome size up to 2.66 Gb and a contig N50 of 1.12 Mb,produced with third-generation PacBio sequencing technology.This is the first chromosome-level genome assembly for the genus Panax.Through genome evolution analysis,we explored phylogenetic and whole-genome duplication events and examined their impact on saponin biosynthesis.We performed a detailed transcriptional analysis of P.notoginseng and explored genelevel mechanisms that regulate the formation of characteristic tubercles.Next,we studied the biosynthesis and regulation of saponins at temporal and spatial levels.We combined multi-omics data to identify genes that encode key enzymes in the P.notoginseng terpenoid biosynthetic pathway.Finally,we identified five glycosyltransferase genes whose products catalyzed the formation of different ginsenosides in P.notoginseng.The genetic information obtained in this study provides a resource for further exploration of the growth characteristics,cultivation,breeding,and saponin biosynthesis of P.notoginseng.展开更多
Sterol C24-methyltransferase(SMT) plays multiple important roles in plant growth and development. SMT1, which belongs to the family of transferases and transforms cycloartenol into 24-methylene cycloartenol, is involv...Sterol C24-methyltransferase(SMT) plays multiple important roles in plant growth and development. SMT1, which belongs to the family of transferases and transforms cycloartenol into 24-methylene cycloartenol, is involved in the biosynthesis of 24-methyl sterols. Here, we report the cloning and characterization of a cDNA encoding a sterol C24-methyltransferase from Tripterygium wilfordii(Tw SMT1). Tw SMT1(Gen Bank access number KU885950) is a 1530 bp cDNA with a 1041 bp open reading frame predicted to encode a 346-amino acid, 38.62 k Da protein. The polypeptide encoded by the SMT1 cDNA was expressed and purified as a recombinant protein from Escherichia coli(E. coli) and showed SMT activity. The expression of Tw SMT1 was highly up-regulated in T. wilfordii cell suspension cultures treated with methyl jasmonate(Me JA). Tissue expression pattern analysis showed higher expression in the phellem layer compared to the other four organs(leaf, stem, xylem and phloem), which is about ten times that of the lowest expression in leaf. The results are meaningful for the study of sterolbiosynthesis of T. wilfordii and will further lay the foundations for the research in regulating both the content of other main compounds and growth and development of T. wilfordii.展开更多
Tripterygium wilfordii is a valuable medicinal plant rich in biologically active diterpenoids,but there are few studies on the origins of these diterpenoids in its secondary metabolism.Here,we identified three regions...Tripterygium wilfordii is a valuable medicinal plant rich in biologically active diterpenoids,but there are few studies on the origins of these diterpenoids in its secondary metabolism.Here,we identified three regions containing tandemly duplicated diterpene synthase genes on chromosomes(Chr) 17 and 21 of T. wilfordii and obtained 11 diterpene synthases with different functions.We farther revealed that these diterpene synthases underwent duplication and rearrangement at approximately 2.3-23.7 million years ago(MYA) by whole-genome triplication(WGT),transposon mediation,and tandem duplication,followed by functional divergence.We first demonstrated that four key amino acids in the sequences of TwCPS3,TwCPS5,and TwCPSS were altered during evolution,leading to their functional divergence and the formation of diterpene secondary metabolites.Then,we demonstrated that the functional divergence of three TwKSLs was driven by mutations in two key amino acids.Finally,we discovered the mechanisms of evolution and pseudogenization of miltiradiene synthases in T.wilfordii and elucidated that the new function in TwMS1/2 from the terpene synthase(TPS)-b subfamily was caused by progressive changes in multiple amino acids after the WGT event.Our results provide key evidence for the formation of diverse diterpenoids during the evolution of secondary metabolites in T.wilfordii.展开更多
Leaf and tuber extracts of Curcuma wenyujin contain a mixture of curcuminoids.However,the curcuminoid constituents and their molecular mechanisms are poorly understood,and the relevant curcumin synthases remain unclea...Leaf and tuber extracts of Curcuma wenyujin contain a mixture of curcuminoids.However,the curcuminoid constituents and their molecular mechanisms are poorly understood,and the relevant curcumin synthases remain unclear.In this study,we comprehensively compared the metabolite profiles of the leaf and tuber tissues of C.wenyujin.A total of 11 curcuminoid metabolites were identified and exhibited differentially changed contents in the leaf and tuber tissues.An integrated analysis of metabolomic and transcriptomic data revealed the proposed biosynthesis pathway of curcuminoid.Two candidate type III polyketide synthases(PKSs)were identified in the metabolically engineering yeasts,indicating that CwPKS1 and CwPKS2 maintained substrate and product specificities.Especially,CwPKS1 is the first type III PKS identified to synthesize hydrogenated derivatives of curcuminoid,dihydrocurcumin and tetrehydrocurcumin.Interestingly,the substitution of the glycine at position 219 with aspartic acid(G219D mutant)resulted in the complete inactivation of CwPKS1.Our results provide the first comparative metabolome analysis of C.wenyujin and functionally identified type III PKSs,giving valuable information for curcuminoids biosynthesis.展开更多
基金support from the National Natural Science Foundation of China(nos.81891010,81891013)the Key Project at central government level:The ability establishment of sustainable use for valuable Chinese medicine resources(no.2060302-1806-03)+1 种基金the High-level Teachers in Beijing Municipal Universities in the Period of 13th Five-year Plan(no.CIT&TCD20170324)the National Program for Special Support of Eminent Professionals.
文摘Panax notoginseng,a perennial herb of the genus Panax in the family Araliaceae,has played an important role in clinical treatment in China for thousands of years because of its extensive pharmacological effects.Here,we report a high-quality reference genome of P.notoginseng,with a genome size up to 2.66 Gb and a contig N50 of 1.12 Mb,produced with third-generation PacBio sequencing technology.This is the first chromosome-level genome assembly for the genus Panax.Through genome evolution analysis,we explored phylogenetic and whole-genome duplication events and examined their impact on saponin biosynthesis.We performed a detailed transcriptional analysis of P.notoginseng and explored genelevel mechanisms that regulate the formation of characteristic tubercles.Next,we studied the biosynthesis and regulation of saponins at temporal and spatial levels.We combined multi-omics data to identify genes that encode key enzymes in the P.notoginseng terpenoid biosynthetic pathway.Finally,we identified five glycosyltransferase genes whose products catalyzed the formation of different ginsenosides in P.notoginseng.The genetic information obtained in this study provides a resource for further exploration of the growth characteristics,cultivation,breeding,and saponin biosynthesis of P.notoginseng.
基金supported by the National Natural Science Foundation of China (81422053 and 81373906 to Wei Gao and 81325023 to Luqi Huang)the Support Project of High-level Teachers in Beijing Municipal Universities in the Period of 13th Five-year Plan (CIT&TCD20170324 to Wei Gao)the Key project at Central Government Level: The Ability Establishment of Sustainable Use for Valuable Chinese Medicine Resources (2060302 to Luqi Huang)
文摘Sterol C24-methyltransferase(SMT) plays multiple important roles in plant growth and development. SMT1, which belongs to the family of transferases and transforms cycloartenol into 24-methylene cycloartenol, is involved in the biosynthesis of 24-methyl sterols. Here, we report the cloning and characterization of a cDNA encoding a sterol C24-methyltransferase from Tripterygium wilfordii(Tw SMT1). Tw SMT1(Gen Bank access number KU885950) is a 1530 bp cDNA with a 1041 bp open reading frame predicted to encode a 346-amino acid, 38.62 k Da protein. The polypeptide encoded by the SMT1 cDNA was expressed and purified as a recombinant protein from Escherichia coli(E. coli) and showed SMT activity. The expression of Tw SMT1 was highly up-regulated in T. wilfordii cell suspension cultures treated with methyl jasmonate(Me JA). Tissue expression pattern analysis showed higher expression in the phellem layer compared to the other four organs(leaf, stem, xylem and phloem), which is about ten times that of the lowest expression in leaf. The results are meaningful for the study of sterolbiosynthesis of T. wilfordii and will further lay the foundations for the research in regulating both the content of other main compounds and growth and development of T. wilfordii.
基金supported by the National Key R&D Program of China (No.2020YFA0908000)the Key Project at central government level: The ability establishment of sustainable use for valuable Chinese medicine resources (No.2060302-1806-03)Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine (ZYYCXTD-D202005)。
文摘Tripterygium wilfordii is a valuable medicinal plant rich in biologically active diterpenoids,but there are few studies on the origins of these diterpenoids in its secondary metabolism.Here,we identified three regions containing tandemly duplicated diterpene synthase genes on chromosomes(Chr) 17 and 21 of T. wilfordii and obtained 11 diterpene synthases with different functions.We farther revealed that these diterpene synthases underwent duplication and rearrangement at approximately 2.3-23.7 million years ago(MYA) by whole-genome triplication(WGT),transposon mediation,and tandem duplication,followed by functional divergence.We first demonstrated that four key amino acids in the sequences of TwCPS3,TwCPS5,and TwCPSS were altered during evolution,leading to their functional divergence and the formation of diterpene secondary metabolites.Then,we demonstrated that the functional divergence of three TwKSLs was driven by mutations in two key amino acids.Finally,we discovered the mechanisms of evolution and pseudogenization of miltiradiene synthases in T.wilfordii and elucidated that the new function in TwMS1/2 from the terpene synthase(TPS)-b subfamily was caused by progressive changes in multiple amino acids after the WGT event.Our results provide key evidence for the formation of diverse diterpenoids during the evolution of secondary metabolites in T.wilfordii.
基金supported by the National Natural Science Foundation of China(82173919,82104320)the Natural Science Foundation of Zhejiang Province(LY21C050004,LQ22H280013).
文摘Leaf and tuber extracts of Curcuma wenyujin contain a mixture of curcuminoids.However,the curcuminoid constituents and their molecular mechanisms are poorly understood,and the relevant curcumin synthases remain unclear.In this study,we comprehensively compared the metabolite profiles of the leaf and tuber tissues of C.wenyujin.A total of 11 curcuminoid metabolites were identified and exhibited differentially changed contents in the leaf and tuber tissues.An integrated analysis of metabolomic and transcriptomic data revealed the proposed biosynthesis pathway of curcuminoid.Two candidate type III polyketide synthases(PKSs)were identified in the metabolically engineering yeasts,indicating that CwPKS1 and CwPKS2 maintained substrate and product specificities.Especially,CwPKS1 is the first type III PKS identified to synthesize hydrogenated derivatives of curcuminoid,dihydrocurcumin and tetrehydrocurcumin.Interestingly,the substitution of the glycine at position 219 with aspartic acid(G219D mutant)resulted in the complete inactivation of CwPKS1.Our results provide the first comparative metabolome analysis of C.wenyujin and functionally identified type III PKSs,giving valuable information for curcuminoids biosynthesis.
