Identification And Expression Analysis Of PhUGT74E1 And PhUGT74E2 In Petunia

Petunia(Petunia hybrida Var.Mitchel diploid)is a genus of Solanaceae,which is an important ornamental plant in garden applications due to its rich color,long flowering period and easy cultivation.The development and resistance of the petunia branch are the hot issues of current research.In this study,petunia was used as a test material,and the petunia glycosyltransferase PhUGT74E1 and PhUGT74E2 genes were cloned.The sequence was analyzed by bioinformatics,and the PhUGT74E1 and PhUGT74E2 genes were expressed in different tissues by real-time fluorescent quantitative PCR.The expression under drought and salt stress treatment was studied.The expression vectors of Ph UGT74E1,Ph UGT74E2 overexpression vector and PhUGT74E2 promoter(pPhUGT74E2)fusion GUS were constructed,and 35S::PhUGT74E2 overexpressing transgenic plants and pPhUGT74E2::GUS transgenic plants were obtained by infecting Arabidopsis thaliana.The main results are as follows:(1)The petunia glycosyltransferase PhUGT74E1 and PhUGT74E2 genes were cloned.PhUGT74E1 contains a 1401 bp open reading frame encoding 466 amino acids.The molecular weight and isoelectric point of the protein were 52.73 kDa and 5.42,respectively.It is speculated that the molecular formula is C2374H3715N609O700S23,and the phylogenetic tree analysis of the relationship between the UGT74E1 protein and the UGT74E1 protein of potato is the closest;PhUGT74E2 contains a 1347 bp open reading frame encoding 448 amino acids.The molecular weight and isoelectric point of the protein were 50.53 kDa and 5.18,respectively.It is speculated that its protein formula is C2278H3544N586O676S18.Phylogenetic tree analysis of the relationship between UGT74E2 protein and tobacco UGT74E2 proteinis.(2)The promoter sequence of Ph UGT74E2 gene was cloned and the length was 2083 bp.The promoter sequence contains a light response element a gibberellin response element,an abscisic acid response element,a protein binding site,and the like.The promoter sequence has four core promoter regions,and the possible transcription initiation sites are A,C,A,and A,respectively,located at 266,987,1613,and 1684.(3)Expression analysis of different tissues and drought and salt stress treatment showed:The PhUGT74E1 has the highest expression in roots and the lowest expression in stems and leaf axil,about 1/10 of the roots;while the expression of Ph UGT74E2 was highest in leaf axil.The lowest expression in apex,about 1/20 of the leaf axil;The expression of PhUGT74E2 was up-regulated to 40.8-fold and 37.6-fold,respectively,after drought and stress treatment for 12 h,and the expression level was at a relatively stable level with time;(4)The expression vectors of PhUGT74E1,PhUGT74E2 overexpression vector and Ph UGT74E2 promoter(pPhUGT74E2)fusion GUS were constructed,and 35S::PhUGT74E2 overexpressing transgenic plants were screened.