Apples often exhibit bitter pits in response to metabolic disorders during ripening and storage;however, the mechanisms underlying the bitter pit(BP) development remain unclear. Here, metabolome and transcriptome anal...Apples often exhibit bitter pits in response to metabolic disorders during ripening and storage;however, the mechanisms underlying the bitter pit(BP) development remain unclear. Here, metabolome and transcriptome analyses were performed to investigate BP pulp of 'Fuji'. Two auxin-response genes, MdGH3.1 and MdSAUR36, were screened. Their expression as well as the auxin content in BP pulp were found to be higher than those in healthy pulp(P < 0.01). In the field, excess CO(NH2)2increased the incidence of BP. Moreover, the auxin content and MdGH3.1 expression increased in apples after nitrogen fertilization. On Day 30 before harvest, the two genes were transiently transferred to the fruit, and 20.69% and 23.21% of BP fruits were harvested. After 10 μmol·L-1auxin was infiltrated at low pressure into postharvest fruit, the increase in MdGH3.1 expression occurred earlier than that in MdSAUR36. MdGH3.1 increased the expression of MdSAUR36, but MdSAUR36 did not increase expression of MdGH3.1. Therefore, we suggest that MdGH3.1 acts upstream of MdSAUR36 during BP formation and that these genes induce BP formation by regulating auxin and phenylpropanoid biosynthesis.展开更多
Salt stress inhibits plant growth and affects the biosynthesis of its secondary metabolites.Flavonoids are natural compounds that possess many important biological activities,playing a significant role in the medicina...Salt stress inhibits plant growth and affects the biosynthesis of its secondary metabolites.Flavonoids are natural compounds that possess many important biological activities,playing a significant role in the medicinal activity of Eucommia ulmoides(E.ulmoides).To investigate the mechanism by which salt stress affects the biosynthesis of flavonoids in E.ulmoides,a comprehensive analysis of metabolomics and transcriptomics was conducted.The results indicated that salt stress led to the wilting and darkening of E.ulmoides leaves,accompanied by a decrease in chlorophyll levels,and significantly induced malondialdehyde(MDA)and relative electrical conductivity.During salt stress,most metabolites in the flavonoid biosynthesis pathway of E.ulmoides were upregulated,indicating that flavonoid biosynthesis is likely the main induced pathway under salt stress.Among them,secondary metabolites such as 6-Hydroxyluteolin and Quercetin are likely key metabolites induced by salt stress.The correlation analysis of transcriptomics and metabolomics revealed that EuSHT is a hub gene induced by salt stress,promoting the production of flavonoids such as 6-Hydroxyluteolin.The co-expression network showed a strong positive correlation between EuSHT and the biosynthesis of 6-Hydroxyluteolin and Quercetin,while it exhibited a negative correlation with Catechin biosynthesis.The branches leading to Luteolin and Dihydroquercetin are likely the main pathways for flavonoid compound biosynthesis in the plant stress response during salt stress.The results of this study provided a preliminary mechanism of secondary metabolites such as flavonoids in the medicinal plant E.ulmoides induced by salt stress and provided new theoretical support for discussing the mechanism of plant stress response.It also provided useful information for subsequent exploration of resistance genes in E.ulmoides.展开更多
Trypsin,a novel superoxide scavenger,significantly enhances the storage quality of Hylocereus undatus(H.undatus).To elucidate the preservation mechanism of trypsin on H.undatus,a widely targeted metabolomic analysis,a...Trypsin,a novel superoxide scavenger,significantly enhances the storage quality of Hylocereus undatus(H.undatus).To elucidate the preservation mechanism of trypsin on H.undatus,a widely targeted metabolomic analysis,and transcriptomics analysis were conducted.Firstly,a total of 453 metabolites were identified,with organic acids and their derivatives constituting the largest proportion(25%).Amino acids and their metabolites,prominent among organic acids,were further analyzed.Among them,73 metabolites were associated with amino acids,and 37 exhibited significant differences.The most enriched Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway was arginine biosynthesis(map00220),with polyamine metabolites showing the most pronounced differences,particularly spermine(FC=1.7594).Compared with the control group,4-hydroxy-2-oxoglutaric acid was significantly upregulated(FC=2.117)in the process of spermine biosynthesis.Furthermore,the results of Gene Ontology(GO)and KEGG enrichment analysis of the H.undatus transcriptome profile revealed that trypsin treatment led to 187 differentially expressed genes associated with arginine.Both GO and KEGG analyses exhibited significant enrichment in the spermine biosynthetic process(GO:0006597)(map:00220)within the arginine biosynthesis pathway.Moreover,most enzymes and metabolites within the spermine biosynthesis pathway in H.undatus were upregulated.The results of the PPI network highlighted that ADC,SPDS,and SAMDC,among others,were pivotal proteins involved in trypsin-regulated arginine metabolism and spermine synthesis.This study revealed that trypsin could significantly delay postharvest senescence of H.undatus at room temperature.This effect might be attributed to trypsin triggering the synthesis of 4-hydroxy-2-oxoglutaric acid in the fruit peel,thereby promoting the biosynthesis of spermine and other polyamines.展开更多
Maize is an essential source of nutrition for humans and animals and is rich in various metabolites that determine its quality.Different maize varieties show significant differences in metabolite content.Two kinds of ...Maize is an essential source of nutrition for humans and animals and is rich in various metabolites that determine its quality.Different maize varieties show significant differences in metabolite content.Two kinds of waxy maize parental materials,S181 and 49B,created by the Chongqing Academy of Agricultural Sciences,are widely grown in China.S181 shows higher starch and sugar contents than 49B.This study generated metabolic profiles to assess the differences between the two varieties.A total of 674 metabolites that were significantly differentially expressed between the two varieties were identified by gas chromatography and untargeted metabolomics technology.These metabolites were associated with 21 categories,including antioxidant metabolites.Moreover,6415 differentially expressed genes(DEGs)were identified by RNA-seq.Interestingly,these DEGs comprised starch and sugar synthesis pathway genes and 72 different transcription factor families.Among these,six families that were reported to play an essential role in plant antioxidant action accounted for 39.2%of the transcription factor families.Using the Kyoto Encyclopedia of Genes and Genomes(KEGG)classification,the DEGs were mainly involved in amino acid biosynthesis,glycolysis/glucose metabolism,and the synthetic and metabolic pathways of antioxidant active substances.Furthermore,the correlation analysis of transcriptome and metabolomics identified five key transcription factors(ZmbHLH172,ZmNAC44,ZmNAC-like18,ZmS1FA2,ZmERF172),one ubiquitin ligase gene(ZmE25A)and one sucrose synthase gene(ZmSS1).They likely contribute to the quality traits of waxy corn through involvement in the metabolic regulatory network of antioxidant substances.Thus,our results provide new insights into maize quality-related antioxidant metabolite networks and have potential applications for waxy corn breeding.展开更多
基金the Agricultural Variety Improvement Project of Shandong Province(Grant No.2019LZGC007)Taishan Scholar Foundation of Shandong Province(Grant No.tstp20221134)China Agriculture Research System Foundation(Grant No.CARS-27).
文摘Apples often exhibit bitter pits in response to metabolic disorders during ripening and storage;however, the mechanisms underlying the bitter pit(BP) development remain unclear. Here, metabolome and transcriptome analyses were performed to investigate BP pulp of 'Fuji'. Two auxin-response genes, MdGH3.1 and MdSAUR36, were screened. Their expression as well as the auxin content in BP pulp were found to be higher than those in healthy pulp(P < 0.01). In the field, excess CO(NH2)2increased the incidence of BP. Moreover, the auxin content and MdGH3.1 expression increased in apples after nitrogen fertilization. On Day 30 before harvest, the two genes were transiently transferred to the fruit, and 20.69% and 23.21% of BP fruits were harvested. After 10 μmol·L-1auxin was infiltrated at low pressure into postharvest fruit, the increase in MdGH3.1 expression occurred earlier than that in MdSAUR36. MdGH3.1 increased the expression of MdSAUR36, but MdSAUR36 did not increase expression of MdGH3.1. Therefore, we suggest that MdGH3.1 acts upstream of MdSAUR36 during BP formation and that these genes induce BP formation by regulating auxin and phenylpropanoid biosynthesis.
基金supported by the National Key Research and Development Program of China(2017YFC1600802)Henan Provincial Science and Technology Research Project,China(No.232102110134).
文摘Salt stress inhibits plant growth and affects the biosynthesis of its secondary metabolites.Flavonoids are natural compounds that possess many important biological activities,playing a significant role in the medicinal activity of Eucommia ulmoides(E.ulmoides).To investigate the mechanism by which salt stress affects the biosynthesis of flavonoids in E.ulmoides,a comprehensive analysis of metabolomics and transcriptomics was conducted.The results indicated that salt stress led to the wilting and darkening of E.ulmoides leaves,accompanied by a decrease in chlorophyll levels,and significantly induced malondialdehyde(MDA)and relative electrical conductivity.During salt stress,most metabolites in the flavonoid biosynthesis pathway of E.ulmoides were upregulated,indicating that flavonoid biosynthesis is likely the main induced pathway under salt stress.Among them,secondary metabolites such as 6-Hydroxyluteolin and Quercetin are likely key metabolites induced by salt stress.The correlation analysis of transcriptomics and metabolomics revealed that EuSHT is a hub gene induced by salt stress,promoting the production of flavonoids such as 6-Hydroxyluteolin.The co-expression network showed a strong positive correlation between EuSHT and the biosynthesis of 6-Hydroxyluteolin and Quercetin,while it exhibited a negative correlation with Catechin biosynthesis.The branches leading to Luteolin and Dihydroquercetin are likely the main pathways for flavonoid compound biosynthesis in the plant stress response during salt stress.The results of this study provided a preliminary mechanism of secondary metabolites such as flavonoids in the medicinal plant E.ulmoides induced by salt stress and provided new theoretical support for discussing the mechanism of plant stress response.It also provided useful information for subsequent exploration of resistance genes in E.ulmoides.
基金the National Key Research and Development Program of China(2017YFC1600802).
文摘Trypsin,a novel superoxide scavenger,significantly enhances the storage quality of Hylocereus undatus(H.undatus).To elucidate the preservation mechanism of trypsin on H.undatus,a widely targeted metabolomic analysis,and transcriptomics analysis were conducted.Firstly,a total of 453 metabolites were identified,with organic acids and their derivatives constituting the largest proportion(25%).Amino acids and their metabolites,prominent among organic acids,were further analyzed.Among them,73 metabolites were associated with amino acids,and 37 exhibited significant differences.The most enriched Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway was arginine biosynthesis(map00220),with polyamine metabolites showing the most pronounced differences,particularly spermine(FC=1.7594).Compared with the control group,4-hydroxy-2-oxoglutaric acid was significantly upregulated(FC=2.117)in the process of spermine biosynthesis.Furthermore,the results of Gene Ontology(GO)and KEGG enrichment analysis of the H.undatus transcriptome profile revealed that trypsin treatment led to 187 differentially expressed genes associated with arginine.Both GO and KEGG analyses exhibited significant enrichment in the spermine biosynthetic process(GO:0006597)(map:00220)within the arginine biosynthesis pathway.Moreover,most enzymes and metabolites within the spermine biosynthesis pathway in H.undatus were upregulated.The results of the PPI network highlighted that ADC,SPDS,and SAMDC,among others,were pivotal proteins involved in trypsin-regulated arginine metabolism and spermine synthesis.This study revealed that trypsin could significantly delay postharvest senescence of H.undatus at room temperature.This effect might be attributed to trypsin triggering the synthesis of 4-hydroxy-2-oxoglutaric acid in the fruit peel,thereby promoting the biosynthesis of spermine and other polyamines.
基金supported by the General Program of Natural Science Foundation of Chongqing(cstc2019jcyj msxmx0468)Chongqing Talents Program—Basic Research and Frontier Exploration(cstc2021ycjh bgzxm0152)+1 种基金Chongqing Agricultural Development Fund Project—Resource Plant New Variety Breeding and Application(NKY-2020AB015)the Fundamental Research Funds for the Central Universities(2022CDJXY-004),China.
文摘Maize is an essential source of nutrition for humans and animals and is rich in various metabolites that determine its quality.Different maize varieties show significant differences in metabolite content.Two kinds of waxy maize parental materials,S181 and 49B,created by the Chongqing Academy of Agricultural Sciences,are widely grown in China.S181 shows higher starch and sugar contents than 49B.This study generated metabolic profiles to assess the differences between the two varieties.A total of 674 metabolites that were significantly differentially expressed between the two varieties were identified by gas chromatography and untargeted metabolomics technology.These metabolites were associated with 21 categories,including antioxidant metabolites.Moreover,6415 differentially expressed genes(DEGs)were identified by RNA-seq.Interestingly,these DEGs comprised starch and sugar synthesis pathway genes and 72 different transcription factor families.Among these,six families that were reported to play an essential role in plant antioxidant action accounted for 39.2%of the transcription factor families.Using the Kyoto Encyclopedia of Genes and Genomes(KEGG)classification,the DEGs were mainly involved in amino acid biosynthesis,glycolysis/glucose metabolism,and the synthetic and metabolic pathways of antioxidant active substances.Furthermore,the correlation analysis of transcriptome and metabolomics identified five key transcription factors(ZmbHLH172,ZmNAC44,ZmNAC-like18,ZmS1FA2,ZmERF172),one ubiquitin ligase gene(ZmE25A)and one sucrose synthase gene(ZmSS1).They likely contribute to the quality traits of waxy corn through involvement in the metabolic regulatory network of antioxidant substances.Thus,our results provide new insights into maize quality-related antioxidant metabolite networks and have potential applications for waxy corn breeding.