Expression Analysis Of Wheat C₂H₂ Zinc Finger Protein Genes Under Abiotic Stress And Preliminary Study On The Function Of TaZFP5

Wheat is an important grain in the world.Its total output,planting area and total trade all rank the top in the world.In recent years,abiotic stresses such as drought,high salinity,high temperature and low temperature have become important factors restricting the yield and quality of wheat.So it is important to obtain high quality wheat.Q-type C₂H₂zinc finger protein,as one of plant transcription factors,plays a crucial role in plant growth and resisting biological and abiotic stresses.C₂H₂zinc finger protein has been widely studied in Arabidopsis thaliana,rice and other plants.However,the function of C₂H₂zinc finger protein in wheat are still unkown.In the previous studies,the Q-type C₂H₂zinc finger protein family of wheat was selected as the research object.In previous reports,47 Q-type C₂H₂zinc finger proteins were screened out,and 30 genes specifically expressed in roots were found through tissue expression analysis.In this study,we studied their expression patterns under the low temperature,salt stress and drought stress.Q-type C2H2 zinc finger protein gene ZFP5 in wheat（TaZFP5）was selected for further study through analysis,and heterooverexpressed homozygous transgenic lines of Arabidopsis thaliana were obtained by using the blotch infection method,named OE-1 and OE-2.The preliminary function of TaZFP5 was further studied,the specific results are as follows:1.Under drought stress（PEG simulation）,the expression levels of 19 ZFP genes were up-regulated and 3 ZFP genes were significantly down-regulated,suggesting that these 22 ZFP genes may be involved in the response of wheat root to drought stress.Under the condition of low temperature stress,the expression levels of 7 ZFP genes were up-regulated and 8 ZFP genes were significantly down-regulated.It was speculated that these 15 ZFP genes might be involved in the response of wheat root to low temperature stress.Under the condition of high salt stress,the expression levels of19 ZFP genes were up-regulated and 5 ZFP genes were down-regulated.It was suggested that these 24 ZFP genes might be involved in the response of wheat root to salt stress.2.According to bioinformatics analysis,TaZFP5 in wheat is a non-transmembrane protein and belongs to Q-type C₂H₂zinc finger protein.It has two zinc finger structures,and the TaZFP5 gene coding region was 570 bp in length and encoded 169 amino acids.The results of specific expression analysis,evolutionary analysis and promoter cis-element analysis indicated that TaZFP5 might be induced by abiotic stresses such as drought,high salinity and low temperature.3.TaZFP5 gene in wheat was cloned successfully,and the fusion expression vector p CAMBIA2300::TaZFP5 with GFP label was constructed,and the results of subcellular localization showed that TaZFP5 was a nuclear protein.4.The PHB::TaZFP5 overexpression vector with GFP label was constructed and heterologously transferred into wild-type Arabidopsis thaliana.The transgenic plants were identified from two different perspectives,DNA level and protein level,and the homozygous transgenic plants of TaZFP5 were obtained.5.The seeds of Arabidopsis wild-type Col-0 and TaZFP5 transgenic genes were treated with some abiotic stress,such as drought,high salt,high temperature and ABA,and the germination rate was calculated.The results showed that the germination rate of seeds in overexpression transgenic plants was lower than that of wild-type seeds.It is speculated that the response of TaZFP5 gene to drought,high salt and high temperature stress during seed germination may be related to ABA signaling pathway.