Transcriptome Analysis Of Genes Involved In Anthocyanins Accumulation In Vitis Davidii

The color of grape berry skin is essentially determined by the components and content of anthocyanins. The fruit color of Chinese wild grapes is generally black, Vitis davidii is the only species that possesses white berry varieties among Chinese wild grape species. In this study, ultra performance liquid chromatography mass spectrometer?UPLC-MS? was used to detect the components and content of anthocyanins at different fruit developmental stages of black and white V. davidii, in order to survey the specificity of the components in the berry skin of V. davidii. The transcriptomic analysis was performed to compare the difference of transcriptional level in the black and white V. davidii, in order to find some key genes that are related to anthocyanins accumulation in V. davidii, and to find the reasons of the appearance of white V. davidii. The main results of this study are as follows:1. Anthocyanin composition in the berry skin of black and white spine grapesA total of 24 kinds of anthocyanins were detected at three fruit developmental stages of black and white spine grapes. With the development of the fruit, the content of anthocyanins is gradually increased. In black spine grape, the major anthocyanin was Malvidin-3,5-O-diglucoside, which accounted for 87% of the total anthocyanins. Trace amount of anthocyanins was also detected in white V. davidii, the major anthocyanins were Delphinidin-3,5-O-diglucoside and Malvidin-3,5-O-diglucoside.2. The results of transcriptome analysisThe results of transcriptome analysis showed that, the expression level of genes related to the anthocyanins accumulation showed significant difference between black and white spine grapes. After the analysis of functional category enrichment and differential expression patterns of differential expression genes?DEGs?, 41 genes were selected as the candidate genes, which were considered to be related to the biosynthesis and transport of anthocyanins in the berry skin of spine grape. Among these candidate genes, 16 genes have been reported as being related to anthocyanins accumulation, such as MYBA1?VIT₀2s0033g00410?, and 25 genes were newly found in our study as probably being related to anthocyanins accumulation in spine grapes, such as MYB4?VIT₀1s0011g04760?. We inferred that 5GT?VIT₀9s0002g06590? was related to the biosynthsis of bis-glucosidic anthocyanins, 3AT?VIT₀3s0017g00870? played an important role in anthocyanin acylation, GST4?VIT₀4s0079g00690? and AM2?VIT₁6s0050g00910? played important roles in anthocyanins transport.As the key gene of anthocyanins biosynthsis, UFGT?VIT₁6s0039g02230? did not express in white spine grape. We inferred 5 putative UDP-glycosyltranferases?UGT? genes?VIT₁7s0000g08100, VIT₀0s0324g00070, VIT₀0s0324g00050, VIT₀6s0004g05780 and VIT₀8s0007g04570? were related to the biosynthsis of anthocyanins in white spine grapes.3. Quantitative real-time PCR validationRelative expression profiles of 30 genes were analyzed by quantitative real-time PCR?q RT-PCR?,and compareing with the results of transcriptome analysis, the results showed that the expression pattern of most of genes were consistent with the results of transcriptome analysis. It proved the reliability of the transcriptome analysis results.