A seed‐specific promoter from allergen gene Fag t 2 in Tartary buckwheat (Fagopyrum tataricum) and its responses to phytohormone

BACKGROUND A major allergen Fag t 2 in Tartary buckwheat is abundant in grains and has the potential to improve drought and disease resistance of Arabidopsis thaliana , which led to the hypothesis that the promoter of Fag t 2 had the function of regulating seed‐specific expression and responding to stress. RESULTS This study successfully cloned the Fag t 2 promoter using genome walking. The functions of the Fag t 2 promoter were investigated through gene gun bombardment, GUS staining and activity detection. The findings revealed that full‐length promoter acted as a seed‐specific promoter. As seed‐specific elements decrease, the seed expression specificity diminishes progressively. The full‐length and truncated promoters exhibited differential responses to phytohormone. However, the responsiveness of promoters varied between the protoplast and A. thaliana , suggesting that the regulatory function of the Fag t 2 promoter in stable transformation system is more complicated. CONCLUSION This results of the present study suggest that Fag t 2 promoter has potential as a seed‐specific promoter, which can be used to activate the expression of functional genes at specific sites when aiming to improve crop yield and quality. The regulatory function of Fag t 2 promoter in plant stress resistance mediated by Fag t 2 should be explored in greater depth.