Anthocyanins are vital secondary metabolites contributing to fruit pigmentation and antioxidative properties.While light is a well-known regulator of anthocyanin biosynthesis,the molecular basis of light-independent a...Anthocyanins are vital secondary metabolites contributing to fruit pigmentation and antioxidative properties.While light is a well-known regulator of anthocyanin biosynthesis,the molecular basis of light-independent anthocyanin accumulation remains underexplored.In this study,integrated analysis of metabolome and transcriptome showed that the anthocyanin content in blueberry(Vaccinium corymbosum‘Bluetta’)fruit was slightly decreased by light-impermeable bagging treatment,while anthocyanin biosynthetic genes were transcriptionally inhibited to different levels,suggesting a slight influence of the bagging treatment on anthocyanin accumulation.Further observation showed that fruit bagging did not alter ethylene production but decreased ABA content.Noticeably,two VcMYBA/MYB1s were not transcriptionally altered by the light-impermeable bagging treatment.Consistently,histochemical GUS analysis and pharmacological manipulation suggested light-independent and ethylene-inducible expression of VcMYBA/MYB1.Moreover,WGCNA analysis revealed 3759 genes positively associated with MYBA/MYB1 such as ethylene-associated genes,etc.Additionally,VcbZIP55s and VcCOP1s were activated and inactivated by the bagging treatment,respectively.These findings provided a framework of light-independent anthocyanin biosynthesis in blueberry fruit.展开更多
Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmn...Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmness.In this study,we conducted comprehensive identification and phylogenetic analysis of 265 Caffeic acid O-methyltransferase(COMT)genes across ten different plant species,including Vaccinium corymbosum and four other Vaccinium species.The results reveal that VcCOMT38 is a promising structural gene for the biosynthesis of lignin in blueberry.An in vitro enzymatic assay of VcCOMT38 demonstrated that it is a special enzyme in the lignin biosynthesis pathway and prefers to use caffeic acid as a substrate over 5-hydroxyferulic acid.Transient overexpression and silencing of VcCOMT38 in Vaccinium corymbosum‘Northland’fruits demonstrated that VcCOMT38 participates in lignin biosynthesis and contributes to both an increased number of immature seeds and enhanced fruit firmness.The heterologous overexpression of VcCOMT38 in Nicotiana benthamiana revealed that this gene could increase the lignin content and the syringyl/guaiacyl(S/G)ratio,which determines the maximum monomer yield during lignin depolymerization.These results highlight VcCOMT38 as a crucial gene in lignin biosynthesis and its potential for improving lignin production in industry through genetically modified woody plants.展开更多
基金funded by the National Key R&D Program of China(Grant No.2022YFD1600500)the National Natural Science Foundation of China(Grant No.32272680).
文摘Anthocyanins are vital secondary metabolites contributing to fruit pigmentation and antioxidative properties.While light is a well-known regulator of anthocyanin biosynthesis,the molecular basis of light-independent anthocyanin accumulation remains underexplored.In this study,integrated analysis of metabolome and transcriptome showed that the anthocyanin content in blueberry(Vaccinium corymbosum‘Bluetta’)fruit was slightly decreased by light-impermeable bagging treatment,while anthocyanin biosynthetic genes were transcriptionally inhibited to different levels,suggesting a slight influence of the bagging treatment on anthocyanin accumulation.Further observation showed that fruit bagging did not alter ethylene production but decreased ABA content.Noticeably,two VcMYBA/MYB1s were not transcriptionally altered by the light-impermeable bagging treatment.Consistently,histochemical GUS analysis and pharmacological manipulation suggested light-independent and ethylene-inducible expression of VcMYBA/MYB1.Moreover,WGCNA analysis revealed 3759 genes positively associated with MYBA/MYB1 such as ethylene-associated genes,etc.Additionally,VcbZIP55s and VcCOP1s were activated and inactivated by the bagging treatment,respectively.These findings provided a framework of light-independent anthocyanin biosynthesis in blueberry fruit.
文摘Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmness.In this study,we conducted comprehensive identification and phylogenetic analysis of 265 Caffeic acid O-methyltransferase(COMT)genes across ten different plant species,including Vaccinium corymbosum and four other Vaccinium species.The results reveal that VcCOMT38 is a promising structural gene for the biosynthesis of lignin in blueberry.An in vitro enzymatic assay of VcCOMT38 demonstrated that it is a special enzyme in the lignin biosynthesis pathway and prefers to use caffeic acid as a substrate over 5-hydroxyferulic acid.Transient overexpression and silencing of VcCOMT38 in Vaccinium corymbosum‘Northland’fruits demonstrated that VcCOMT38 participates in lignin biosynthesis and contributes to both an increased number of immature seeds and enhanced fruit firmness.The heterologous overexpression of VcCOMT38 in Nicotiana benthamiana revealed that this gene could increase the lignin content and the syringyl/guaiacyl(S/G)ratio,which determines the maximum monomer yield during lignin depolymerization.These results highlight VcCOMT38 as a crucial gene in lignin biosynthesis and its potential for improving lignin production in industry through genetically modified woody plants.
