小麦和偃麦草TIR基因家族的系统鉴定与表达分析OA

Proteins containing the toll/interleukin-1 receptor(TIR)domain are critical components of the plant immune system.However,the TIR gene family in wheat and its wild relative Thinopyrum species remains poorly characterized.In this study,we systematically identified the TIR genes in common wheat,Thinopyrum elongatum,Thinopyrum intermedium,and Thinopyrum ponticum by using genome and RNA-seq data,and further analyzed their evolutionary relationships and expression patterns.The results showed that TIR genes in common wheat,Th.elongatum,and Th.intermedium are highly conserved in both number and structure,with each subgenome containing four members(TIR1,TNP1,TNP2,and TNP3).In contrast,a significant expansion of TIR genes occurred in Th.ponticum,where 54 TIR genes were identified;the greatest expansion was observed in the TpTIR1 clade.Expression profiling showed that TNP1 genes are highly and constitutively expressed across va-rious tissues,suggesting their involvement in plant growth and development.Conversely,TIR1 genes were barely expressed under infection of powdery mildew and stripe rust,but were strongly in-duced by Fusarium graminearum inoculation.Collectively,our findings reveal the constitution and evolutionary characteristics of TIR genes in wheat and Thinopyrum species,and provide a foundation for investigating the functional divergence of this gene family.