Study On The Antagonism Of ABA And NO Regulating The Changes Of Lycium Fruit Anthocyanin Content

Wolfberry(Lycium)is a plant of the Solanaceae Lycium barbarum.It is a traditional Chinese medicinal material in my country.It has a rich variety of fruit colors and is an excellent material for studying fruit color changes.The accumulation of pigment content in the fruit ripening process of wolfberry determines the change of fruit color.It is well known that both ABA and NO play a very important role in the maturation of plants,and both of them interact or antagonize many physiological changes in the plant,but the relationship between the two in the adjustment of fruit color There are few reports.In this study,three fruits of the Lycium genus with different colors were selected: Lycium barbarum,Lycium barbarum L.var.auranticarpum and Lycium ruthenicum Murr as experimental materials,using physiological and molecular genetics Means,to study the role of signal molecules ABA and NO in the color change of wolfberry fruit and the way of regulation.The main results of the test are as follows:(1)Using the above three wolfberry fruits as materials,through external application of ABA,halidone(ABA synthesis inhibitor)and virus-induced gene silencing,it was found that the ABA content and anthocyanin during the maturation of wolfberry fruits.The content and transcription level of Lb NCED1 are positively correlated.When exogenously applied ABA treatment,the anthocyanin content in wolfberry fruit was significantly increased compared with the untreated group,while the anthocyanin content in the ABA biosynthesis inhibitor halridone treatment group was significantly decreased compared with the control group.Related MYB-b HLH-WD40 transcription complexes AN2,AN1 b and JAF13,and anthocyanin biosynthesis structural genes Lr UF3 GT,Lr DFR,Lr F3 H,Lr CHS,Lr CHI and Lr ANS expression levels change trends consistent with the changes in anthocyanin content.When the Lb NCED1 gene is silenced,it can significantly slow down the fruit coloration during maturity of Lycium barbarum,and reduce the accumulation of anthocyanins and ABA.The results of q RT-PCR detection also showed that silencing the Lb NCED1 gene reduced the transcript levels of the above-mentioned anthocyanin synthesis structural genes and transcription factors.It shows that ABA can activate the transcription levels of AN2,AN1 b and JAF13 in Lycium barbarum fruits,up-regulate the expression of anthocyanin synthesis structural genes,and positively regulate the color changes of fruits.(2)Using the same material of Lycium barbarum fruit,by applying SNP and gene silencing two methods,it was found that the Lb NR expression level and NO concentration were negatively correlated with the anthocyanin content during the maturation of Lycium barbarum fruit,but positively correlated with the proanthocyanidin content.After external application of SNP,the anthocyanin content in the fruit of Lycium barbarum decreased,the transcription factors related to anthocyanin synthesis AN2,AN1 b and JAF13,and the expression levels of anthocyanin biosynthesis genes Lr UF3 GT,Lr DFR,Lr F3 H,Lr CHS,Lr CHI and Lr ANS also had Decreased significantly.When the virus induced gene silencing of the Lb NR gene,the NO concentration in the fruit decreased,the fruit ripening of Lycium barbarum was earlier,and the anthocyanin content in the fruit increased.The q RT-PCR test results also showed that the transcripts of anthocyanin synthesis structural genes and transcription factors increased significantly under this treatment.(3)Using Lycium ruthenicum as the material,the transcription levels of proanthocyanidin synthesis-related transcription factors Lr MYB30,Lr TTG1-like and proanthocyanidin synthesis structural genes Lb LAR and Lb ANR were measured during the maturation process,and the NO content and Lb NR were found through cluster analysis and correlation analysis There is a high positive correlation between the expression level and the expression level of genes related to procyanidin synthesis,and there is a high negative correlation between the expression levels of genes related to anthocyanin synthesis.It shows that NO can transcriptionally activate proanthocyanidin-related transcription factors in Lycium barbarum fruit,up-regulate the expression of proanthocyanidin synthesis structural genes,increase the proanthocyanidin content in the fruit,reduce the expression of anthocyanin synthesis genes,reduce the anthocyanin content,and negatively regulate fruit color.