Genome-wide Identification And Expression Analysis Of The WRKY Gene Family In Sunflower

Bioinformatics analysis of WRKY transcription factor gene family Helianthus annuus based on bio-genomics database was carried out,including the basic physiochemical properties,phylogenetic relationships,codon preference,etc.The chromosomal localization of sunflower WRKY gene was explored,conservative elements,distribution of exons and introns,and gene cis-acting element of the WRKY family members were analyzed;Furthermore,rust-resistant related WRKY genes were screened to provide reference for rust-resistant breeding.1.A total of 127 WRKY transcription factors in the whole genome of the sunflower were found,The phylogenetic tree was constructed for cluster analysis,it could be divided into ?,? and ? groups according to their structural characteristics.WRKY transcription factors in sunflower are widely distributed on 17 chromosomes.All 127 WRKY transcription factors are hydrophilic proteins.The sunflower WRKY family contain 20 conservative elements,three of which are WRKY boxes.The sunflower WRKY gene contain two to six exons.Through analysis,WRKY gene cis-acting elements include,low temperature induction elements,elements necessary for anaerobic induction,gibberellin response elements,auxin response elements,participate in defense and stress response,salicylic acid response,and abscisic acid response specific action elements.2.The sunflower WRKY genes use A/T(U)to end with a codon more than the G/C,and the ENC average is 53.96.The overall preference is weak but the third base prefers to use A/T(U)at the end.By the synonymous codon usage frequency analysis,the third codon ending in A and T account for the highest proportion of codons(RSCU>1).The ENC-GC3s profile indicates that base mutations is a key factor influencing codon preference.3.Using qRT-PCR technology to analyze the expression levels of the 13 selected WRKY transcription factors,the result showed the expression of 11 genes in rust-resistant varieties were significantly higher than the susceptible one,which proved that these 11 genes might play an important role in the rust-resistant response.This study systematically identified the WRKY family of sunflower.And provided a reference for further study on the function and interaction of WRKY transcription factors in sunflower.