The Molecular Mechanism Of The Synthesis And Regulation Of Anthocyanin In The Peel Of Jujube ’Tailihong’

Chinese jujube(Ziziphus jujuba Mill.)is a unique economic forest fruit native to my country.Jujube fruit is rich in nutrition and can be used for both medicine and food.Anthocyanins are flavonoids that give plants a variety of colors and also have health-care functions for the human body.In order to clarify the regulation mechanism of jujube peel anthocyanin synthesis,using ’Tailihong’ as the test material,high performance liquid chromatography(HPLC)was used to determine the anthocyanin content in the peel and different tissues,and real-time fluorescent quantitative PCR(q RT-PCR)comparing the expression patterns of related genes,screening of yeast two-hybrid library and yeast rotation test to study the interaction proteins with Zjb HLHs,the research of the thesis obtained the following results.1.Anthocyanin dynamics and biosynthesis related genes during fruit ripening of’Tailihong’ jujube.Three kinds of anthocyanins were detected in the peel of ’Tailihong’ by HPLC,namely cyanidin 3-O-glucoside,cyanidin 3-O-rutinoside,and peonidin 3,5-Odiglucoside.The result of anthocyanin content determination showed that anthocyanin expression patterns in different periods found that the total anthocyanin content and the content of each anthocyanin component accumulated more in the early stage of fruit development,and relatively less in the later stage.The q RT-PCR analysis found that structural genes related to anthocyanin biosynthesis are expressed in the peel of ’Tailihong’ jujube,but the expression amount and expression trend are different.Correlation analysis showed that the expression patterns of ZjANS1,ZjDFR and ZjUFGT genes were significantly positively correlated with anthocyanin content.2.The regulation analysis of MYB transcription factor ZjTT2 in the synthesis of anthocyanin in ’Tailihong’.One candidate transcription factor ZjTT2 was obtained through transcriptome data.q RT-PCR analysis found that ZjTT2 has tissue specificity,high expression in buds,young leaves and stems,low expression in matured leaves and flowers,and its expression pattern in different fruit development stages is similar to anthocyanin,and showed a downward trend in the early stage.Tobacco transient expression experiments showed that ZjTT2 can be expressed cooperatively with b HLH transcription factor ZjGL3 a or ZjTT8 to promote the accumulation of anthocyanin.The dual luciferase report test shows that the ZjTT2 injection alone will not significantly activate the ZjANS1 promoter activity,but after adding b HLH transcription factor ZjGL3 a or ZjTT8,the ability to activate the ZjANS1 promoter was significantly improved.3.Yeast two-hybrid library screening for interacting proteins.The synergistic b HLH transcription factor of ZjTT2 was screened for yeast two-hybrid and yeast rotation verification,and finally two candidate proteins that interacted with ZjGL3 a were identified,namely ZjAGL1 and ZjAP2.In summary,the identification found that the MYB transcription factor ZjTT2 plays an important role in regulating the anthocyanin synthesis of jujube peel,and obtains the interaction protein with Zjb HLHs(ZjTT8 and ZjGL3a),which deepens the biosynthesis of anthocyanin in the peel of ’Tailihong’.The understanding of regulation provides a basis for the accumulation mechanism of jujube peel anthocyanin.