Genome-wide identification and expression analysis of wheat NPR1 gene family

【Objective】 The identification and expression analysis of NPR1 gene family members in wheat provided theoretical reference for exploring the mechanism of this family gene and wheat genetic improvement.【Method】 Wheat NPR1 gene family members from wheat genome were identified based on NPR1 family protein sequence from arabidopsis. The sequence characteristics were analyzed by bioinformatics software, and the expression levels of wheat NPR1 family genes under different tissues and different stresses were analyzed by RNA-Seq data and real-time fluorescence quantitative PCR(qRT-PCR). The online website STRING was used to predict and analyze the interaction relationship between related proteins of TaNPR1 family members.【Result】 A total of 20 members of wheat NPR1 gene family were identified,and the TaNPR1s encoded by them were unstable proteins with instability index greater than 40. The average total hydrophilic value(GRAVY)was negative(except TaNPR5-D was positive),which was hydrophilic protein. It was mainly distributed in the nucleus,chloroplast,mitochondria,endoplasmic reticulum and cytoplasm. The secondary structure was composed of α-helix,extended strand,β-turn and random coil,and α-helix and random coil were the main components. There were 10 kinds of tertiary structure models. All 20 TaNPR1s proteins could interact with the transcription factor HBP-1b and unknown proteins A,B,C and D,the five proteins all contained bZIP domain (containing TGACG motif)and seed dormancy specific gene domain(DOG1). The expression pattern of TaNPR1s gene in different tissues was different,which could be divided into three categories:expressed in multiple tissues,expressed in specific tissues or developmental stages,and all low expression or no expression in different tissue development stages. Among the 8 randomly selected TaNPR1s genes,the expression levels of 3 genes decreased under Fusarium graminearum stress,but increased under powdery mildew stress. The expression levels of two genes increased under both strains,and the expression levels of two genes decreased under both strains. TaNPR1s gene responded to all six abiotic stress treatments,but their expression patterns were different.【Conclusion】 Members of wheat NPR1 gene family play an important role in regulating the growth and development of different tissues and the response to biological and abiotic stresses,and the variable spliceosomes of genes also show different tissue expression characteristics,enriching the function of NPR1s protein. TaNPR1s protein may play its biological function by binding to bZIP and DOG1 domains.