Identification of Salt Resistance Functional of Grape Transcription Factor VvERF2
[Objective]In order to give references for future study on the mechanism of the AP2/ERF superfamily on grapes,the protein bioinformatics analysis of grape transcription factor VvERF2 was performed.Additionally,the procedures of gene cloning and homologous genetic transformation were employed for exploring the function of VvERF2 under salt stress in grape callus.[Method]For the bioinformatics analysis of the VvERF2 protein,the NCBI Blast database(https://blast.ncbi.nlm.nih.gov/Blast.cgi)and additional online resources were utilized.The Thompson seedless(Vitis vinifera L.)callus was used as the material,and the grape homologous genetic transformation system of VvERF2 were constructed.The transgenic callus phenotype was determined by growth volume,total sugar,total acid,and other factors.Free proline,antioxidant enzyme activity,and other indices were used to assess the salt tolerance of transgenic callus.[Result]Based on the bioinformatical analysis of VvERF2 and the 7 most homologous orthologous protein sequences,the VvERF2 gene encoded 240 amino acids,which were quite similar to those of tomatoes and figs,with protein homology percentages of 78%and 67%,respectively.The amino acid residues in eight species varied from 240 to 348,their molecular weights from 26.43 to 38.60 kDa,their theoretical isoelectric points from 5.54 to 8.68,and their index of fatty amino acids were all belonged to unstable proteins,which was higher than 66%.The physicochemical properties of amino acid sequences in different species were quite different.In addition,the promoter of VvERF2 gene had a variety of cis-acting element related to abscisic acid and other transcription factors,such as MYB.Particularly,VvERF2 expressed specificity in different tissues,with callus exhibiting the lowest level of expression.Following salt stress,however,VvERF2 gene expression increased to three times that of the control group.Transgenic results showed that after overexpression of VvERF2 gene in grape callus,growth amount,total acid,total phenol content and antioxidant activity of DPPH(1,1-diphenyl-2-trinitrophenylhydrazine)were significantly increased.The content of total protein and free proline in transgenic callus were almost higher than those in wild-type callus treated with different concentrations of NaCl.[Conclusion]The overexpression of VvERF2 promoted callus growth and accumulation of secondary metabolites,such as phenolic substances,and improved salt tolerance of grape.
国家科技期刊平台
NSTL
万方数据
维普
