小麦GPX基因鉴定、表达与自然等位变异分析OA

Enhancing glutathione peroxidase(GPX)activity is a promising strategy for developing selenium-enriched wheat(Triticum aestivum L.).To identify members of the wheat GPX gene family and characterize their expression patterns across tissues,developmental stages,and selenium(Se)treatments,this study integrated bioinformatics and molecular biology approaches to systematically characterize e the structure,physicochemical properties,and functional expression of TaGPX genes.Fourteen GPX genes were detected in common wheat,unevenly distributed across chromosomes 2,4,6,and 7 of the A,B,and D homologous groups.Comparative analysis showed that TaGPX genes located on homologous chromosomes were predominantly localized to chloroplasts and chromosomes,with 5 to 6 exons and similar motif numbers.Promoter cis-acting element prediction indicated that most aGPX genes harbor abundant regulatory elements responsive to abiotic stress.By constructing a GPX evolutionary tree,it was found that wheat GPX genes are most closely related to those of Aegilops tauschii,with high similarity in gene differentiation.Transcriptome data showed that most TaGPX genes are highly expressed in leaves,with the highest expression levels at the flag leaf and wax ripening stage,suggesting the involvement of this gene family in scavenging reactive oxygen species(ROS)clearance within chloroplasts.The expression level of TaGPX genes in leaves was significantly higher than in seeds.Integrative analysis of genomic variation and transcriptome profiles implied that the SNP variations in TaGPX genes may contribute to improved ROS detoxification capacity in wheat system itself.Quantitative expression analysis across tissues and selenium salt treatment showed that TaGPX3.2A had the highest relative expression level.It was speculated that sulfur would compete with selenium for absorption sites under selenium supplementation,thereby limiting selenium absorption.De-sulfurization combined with selenium application could increase the expression level of TaGPX genes.This study laid a foundation for leveraging TaGPX genes to improve selenium biofortification in wheat.