Identification And Expression Analysis Of WRKY Gene Family In Solanum Lycopersicum

WRKY transcription factor gene family is a unique gene family in plants.Its most significant characteristics include highly conserved heptapeptide sequence "WRKYGQK" in N-terminal and C2H2 or c2 hc zinc finger motif in C-terminal after heptapeptide sequence,According to the difference of conserved domains,WRKY gene family can be divided into three groups Group Ⅰ,group Ⅱ(Ⅱa + Ⅱb,Ⅱc,Ⅱd+ Ⅱe)and group Ⅲ.WRKY transcription factors not only mediate defense regulation,but also play an important role in plant growth and development.Tomato(Solanum lycopersicum)is an important economic crop.The yield of Tomato in China is about 1 / 4 of that in the world.Therefore,exploring the potential function of genes will provide important theoretical support for improving tomato yield,quality and resistance to stress.In this paper,the WRKY gene family of tomato was re-identified and analyzed by bioinformatics.The expression of Sl WRKY gene in different tissues,organs and developmental stages of tomato and its response to stress were analyzed.The specific research results are as follows:1.In this study,bioinformatics analysis was used to re-identify the members of WRKY gene family in the pdated tomato genome,and 88 members of WRKY gene family were identified and analyzed.Finally,86 members were obtained.By comparing with the results of previous identification,the reasons for the differences were found.Comparing the number and sequence of WRKY gene family members predicted by different versions of tomato genome documents,we found that the number and protein sequence of WRKY gene family members predicted by different versions of tomato genome documents were very different.However,the reasons for the differences are not all caused by the prediction errors.The existence of some family members isoforms also indicates that the members of the tomato WRKY gene family may be regulated by alternative splicing in the post transcriptional regulation process.2.Cluster analysis with WRKY family members of Arabidopsis thaliana family verified the reliability of 86 WRKY gene family members grouping in tomato.Meme analysis showed that there were specific motifs in IIe,suggesting that these motifs may play a unique role in regulating tomato growth and development or defense response by Sl WRKY protein.In addition,the secondary structure analysis of Sl WRKY gene family members showed that the number of regular random coil,α-helix,extended chain and β-fold of different Sl WRKY protein secondary structures were significantly different.The secondary structure of Sl WRKY protein may directly affect the spatial configuration and function of Sl WRKY protein.These results provide an important theoretical basis for further study on the functions of different Sl WRKY proteins in tomato growth and development and response to abiotic and biotic stresses.3.In this study,the expression of Sl WRKY gene in 30 different tissues,organs and developmental stages of tomato was analyzed.It was found that the expression of Sl WRKY transcription factor was significantly different in different tissues,organs and development stages of tomato.Except for a few genes,such as Sl WRKY3-6,Sl WRKY6-1,Sl WRKY7-7 and Sl WRKY8-1,which were highly expressed in various tissues,most of the other genes showed significant tissue,organ or developmental specificity.In this way,there are many WRKY genes that are specifically expressed in specific tissues and organs and have significant changes in expression at different development stages,which indicates that the members of tomato WRKY gene family can be regulated by different expression patterns in the regulation of tomato growth and development.By analyzing the transcriptome data of tomato leaves under abiotic and biotic stress in NCBI SRA database,the results showed that many members of Sl WRKY family could respond to various stress induction.In this study,through the expression analysis of 86 Sl WRKY gene family members in tomato,the Sl WRKY gene involved in tomato growth and development and stress response was basically identified,providing an important theoretical basis for further research on the regulatory network of different Sl WRKY genes in different stages of tomato pistil and stamen growth and development.4.According to the TPM values of the transcriptome data of different tissues and developmental stages in tomato,18 differentially expressed genes were selected for fluorescence quantitative analysis.The results of fluorescence quantitative analysis showed that there was no significant difference in the expression of WRKY gene Sl WRKY8-1 in young and mature pistils and stamens,but there were significant differences in the expression of other 17 genes in young and mature pistils and stamens.Among them,the relative expression of 5 genes in pistil was higher than that in stamen,while the relative expression of 12 genes in stamen was higher than that in pistil.There were significant differences in the expression of 9 genes between young and mature pistils.Among them,the relative expression of 6 genes in young pistil was higher than that in mature pistil,and the relative expression of 3 genes in mature pistil was higher than that in young pistil.There were significant differences in the expression of 11 genes between young and mature stamens.Among them,the relative expression of 3 genes in young stamens was significantly higher than that in mature stamens,while the relative expression of 8 genes in mature stamens was significantly higher than that in young stamens.