Functional analysis of the StWRKY70 gene promoter in potato

GENG Deying; GUO Yuheng; LIU Shipeng; ZHAO Yaqian; ZHAO Dongmei; LI Qian; YANG Zhihui

doi:10.16861/j.cnki.zggc.2025.0156

Abstract：The transcription factor StWRKY70 is involved in plant disease resistance defense responses and can enhance potato early blight resistance.To investigate the promoter function of the potato StWRKY70 gene promoter,this study cloned the promoter sequence using PCR method and predicted its cis-acting elements using online to analyze the distribu-tion characteristics of regulatory elements.Additionally,5'-end deletion expression vector of the promoter(pGreenII 0800-StWRKY70pro::LUC)were constructed.The expression of the reporter gene LUC was observed through transient transformation of tobacco leaves to identify the promoter's active regions.The results showed that the length of the pro-moter sequence was 2000 bp,and contained various stress-responsive cis-elements,such as dehydration-responsive ele-ment MYB,drought-responsive element AP2/ERF,and high-temperature-responsive element HSF.The analysis results of LUC fluorescence intensity showed that with the increase of the length of different 5'-end deletion fragments of the St-WRKY70 gene promoter,the LUC fluorescence intensity gradually increased,indicating that the core region of the St-WRKY70 promoter was 400 bp to 700 bp.In conclusion,the core region and various stress-responsive cis-acting elements of the StWRKY70 gene promoter may be involved in the potato's defense response against early blight by regulating gene transcription efficiency,thereby providing certain theoretical support for further elucidating the mechanism underlying the role of StWRKY70 in plant disease resistance.