Study On The Anthocyanins Metabolism And The Regulation Of Relative Genes In The Fruit Of Apple (Malus Pumila Mill.)

Anthocyanins is a kind of flavonoid substance, which decides the main pigments of the fruit color. The anthocyanins’synthesis is regulated by the relevant synthetase, and a number of studies have discussed the function of the synthetic gene, but there is lacked for the relationship between the synthetic genes. This study used apple fruit (Malus Domestica Borkh CV. Starkrimson)"Starkrimson" as the experimental material, to study the anthocyanin metabolism and relative gene expression in different stages of apple development. Also the apples of "Starkrimson" and "Orin" were treated with bagging and determined for the content change of anthocyanidins and relative gene expression. Then we established the RNA interference of PAL, CHI, DFR and ANS genes using VIGS method and transfected the "Starkrimson" fruits, and determine the relative gene expression change and accumulation content change of anthocyanins plus flavonoids substances of the interfered fruits, to analyze the relationship between anthocyanin metabolism and structure genes, and the relationship of structure genes. The main results and conclusions were as follows:1. Through the analysis to the peel determination of anthocyanins and other flavonoids substances in "Starkrimson" fruits among different periods, we found that with the fruit ripen, the anthocyanin increased nearly692times, the flavonoids substance content increased one time, but phenolic acids, flavanols and phlorizin dihydrate substances showed different levels of decreasing.2. The "Starkrimson" fruits were easier to color after the bagging treatment, we determined the relative structure gene expression and found that the gene expression of PAL, CHS, CHI, F3H, DFR, ANS and UFGT in the bagging fruits increased with different levels after the bag removal. In the stage of fruit ripen, the DFR, ANS and UFGT gene expression increased most significantly, which were8,17and8times more than the content when the bags were just removed, and were2,3and1.7times of the controlled fruits. The results showed that the "Starkrimson" fruits were easier to color due to the gene expression of DFR, ANS and UFGT."Orin" fruits could color after bagging treatment, and the gene expression of PAL, CHS, CHI, F3H, DFR, ANS and UFGT in the bagging fruits increased with different levels after the bag removal. Among them, the DFR, ANS and UFGT gene expression increased most significantly, but the CHS, DFR, ANS and UFGT gene could not nearly be detected in the controlled fruit. Furthermore, the gene expression patterns of DFR, ANS and UFGT were similar to the anthocyanidin content change patterns in "Orin" apple fruits with bag treatment, which indicated that the DFR, ANS and ANS play a key role in the fruit coloring.3. After the interference of PAL, CHI, DFR and ANS gene in the "Starkrimson" fruits, their expression amount decreased, such as PAL decreased by82.8%, CHI by75.3%, DFR by72.3%and ANS98.1%. Furthermore the interference can lead to the decrease of the amount of other gene expression in the metabolic pathway. The results showed that the expression of related genes determined the metabolic pathways of anthocyanins, and they controlled the synthesis of anthocyanins together.4. The RNAi vectors were set up for flavonoids synthase gene PAL, CHI, DFR and ANS and transfected the "Starkrimson" fruits, respectively, then the anthocyanins and other flavonoids substances content were lower, especially the anthocyanins decreased mostly by85.8%-99.5%. The flavanols, flavonoides and Phlorizin dihydrate decreased by29.8%-69.7%,59.6%-92.1%and33.3%-39.5%, respectively. The results showed that the interference of single genes would stop the flavonoids material synthesis.