| In this study,the Ningqi No.1" Lycium barbarum fruits from Ningxia,Qinghai,and Gansu have measured the total phenols and flavonoid contents.And the berries were performed to analyze the relationship between key metabolites,proteins,and genes by metabolomics,proteomics,and transcriptomics.The aim was to investigate the differences in flavonoid biosynthesis mechanisms in Lycium barbarum fruits from different areas.The main results were as follows:(1)The contents of total flavonoid and phenolic were determined using a spectrophotometer.The results showed that the contents of Ningxia berries(57.87 μg/g and 183.41μg/g)were higher than Qinghai(50.77 μg/g and 156.81 μg/g)and Gansu berries(47.86 μg/g and 111.17 μg/g).Based on the UPLC-MS/MS technique,the 105 DAFs were detected in goji berries,including flavones(41%),flavonols(25.7%),and flavanones(10.5%).We further screened the top 30 different flavonoid metabolites.The result found that gossypetin-3-O-rutinoside,isorhamnetin,and delphinidin-3,5,3’-Tri-O-glucoside were the major flavonoid compounds in Ningxia berries and Qinghai berries.The KEGG classification analysis revealed the pathways of flavonoid biosynthesis and flavone and flavonol biosynthesis contributed to a great extent to the change in flavonoid accumulation of goji berries among Ningxia,Qinghai,and Gansu.(2)Based on TMT combined with LC-MS/MS technique,we explored the protein differences in goji berries.A total of 716 DEPs were identified in the three comparison groups.The GO functional annotation and KEGG functional annotation showed that most of the DEPs were annotated to the secondary metabolic processes and biosynthetic pathways of other secondary metabolites.The KEGG enrichment result suggested four metabolic pathways that might be related to flavonoid accumulation in goji berries.In detail,the phenylpropanoid biosynthesis pathway was significantly enriched(P-value<0.05),indicating that the phenylpropane biosynthesis pathway may make a significant contribution to the flavonoid synthesis in Lycium barbarum.We further screened 24 key DEPs related to flavonoid synthesis and found that PAL,C4H,CHI,and CHS were important DEPs for the differences in flavonoid biosynthesis in berries.(3)Based on transcriptome sequencing technology,we investigated the genetic differences between different areas of goji berries.A total of 1858 DEGs were identified.The GO functional annotation results showed that the DEGs of each comparative group were mainly annotated in secondary metabolic processes.The result of KEGG enrichment indicated that three metabolic pathways that might be related to flavonoid accumulation in goji berries.In detail,the DEGs were mainly annotated in the phenylpropanoid biosynthesis pathway.We further discovered that 42 candidate genes related to the three pathways.CHI,CHS,and FLS genes might be key DEGs involved in the biosynthesis of flavonoids in goji from different areas.And FLS gene may be one of the factors for the difference in flavonol compounds in Qinghai,Gansu,and Ningxia berries.The MYB and bHLH transcription factors were the main families regulating the flavonoid synthesis in goji.The correlation results of key DEGs and transcription factors suggested that key structural genes and key regulatory factors were jointly involved in the differences in flavonoid biosynthesis of goji berries from different origins.(4)To investigate the differences in flavonoid biosynthesis of goji berries from different origins based on combined multi-omics analysis techniques.The analysis of combined transcriptomics and proteomics revealed that glucosyltransferase,chalcone isomerase,and anthocyanin 3-O-glucosyltransferase may jointly regulate flavonoid synthesis in berries through both protein and gene levels.In addition,other regulatory relationships between transcriptomics and proteomics were found in addition to the one-to-one interrelationship.The combined transcriptome and metabolome analysis indicated that the FLS,CHI,and CHS genes positively regulated the contents of isorhamnetin and delphinidin-3,5,3’-Tri-O-glucoside.FLS gene could promote the flavonol compounds synthesis in Lycium barbarum.GST gene might be not only involved in the flavonoid synthesis of goji berries but also play a negative regulatory role.Most of the MYB family may promote flavonoid synthesis,while the bHLH family may inhibit flavonoid production in berries.Among them,MYB1 might be an important transcription factor for flavonol biosynthesis in goji berries. |
