AUTHOR=Zhao Jia , Zhang Heng , Zhang Xu , Wang Zongkuan , Niu Ying , Chen Yiming , Sun Li , Wang Haiyan , Wang Xiue , Xiao Jin 

TITLE=The Exocyst Complex Subunit EXO70E1-V From Haynaldia villosa Interacts With Wheat Powdery Mildew Resistance Gene CMPG1-V

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.652337

DOI=10.3389/fpls.2021.652337

ISSN=1664-462X

ABSTRACT=<p>EXO70 belongs to the exocyst complex subunit that plays a critical role in regulating plant cell polarity establishment and defense response. A previous study proved that the E3 ligase CMPG1-V from <italic>Haynaldia villosa</italic>, a diploid wheat relative, positively regulates the resistance to wheat powdery mildew (<italic>Pm</italic>), caused by fungus <italic>Blumeria graminis</italic> f.sp <italic>tritici</italic> (<italic>Bgt</italic>). In this study, a member of EXO70 superfamily named <italic>EXO70E1-V</italic> was isolated from <italic>H. villosa</italic>, and <italic>EXO70E1-V</italic> interacted with CMPG1-V were shown by yeast two-hybrid (Y2H), pull-down assay, bimolecular fluorescence complementation (BiFC) assay, and luciferase complementation imaging (LCI) assay. It is localized in various subcellular organs, i.e., plasma membrane (PM) and endoplasmic reticulum. Co-expression of EXO70E1-V and CMPG1-V showed dot-like structure fluorescence signals that were mainly in PM and nucleus. Expression of <italic>EXO70E1-V</italic> was relatively higher in leaf and was significantly induced by <italic>Bgt</italic> infection and exogenous application of hormones such as salicylic acid. Transient or stable overexpression of <italic>EXO70E1-V</italic> could not enhance/decrease the <italic>Pm</italic> resistance level, suggesting overexpression of EXO70E1-V alone has no impact on <italic>Pm</italic> resistance in wheat.</p>