Respiratory burst oxidase homologs (RBOHs) are key regulators in plant immunity, responsible for catalyzing the production of reactive oxygen species (ROS). In this study, 18 StRBOH genes were identified in the potato genome, distributed across seven chromosomes and exhibiting species-specific evolutionary traits. Tissue-specific expression analysis revealed that StRBOH17 (also referred to as StRBOHA ) was highly expressed in leaves, suggesting its potential role in leaf immune defense. Sequence and structural analyses indicated that StRBOH17 shares conserved homology with AtRBOHF, OsRBOHA/C, and SmRBOHA, supporting functional conservation within subfamilies. Functional studies demonstrated that CRISPR-Cas9-mediated knockdown of StRBOH17 significantly reduced resistance to Phytophthora infestans and decreased ROS accumulation at infection sites. The physical interaction between the StBIK1 kinase and StRBOH17 was confirmed through a combination of predictive analysis and experimental assays, including yeast two-hybrid (Y2H), bimolecular fluorescence complementation (BiFC), and co-immunoprecipitation (Co-IP). This study preliminarily reveals the molecular regulatory mechanism of the “StBIK1–StRBOH17–ROS” module in potato late blight resistance. These findings not only provide direct experimental evidence and a theoretical basis for elucidating how StBIK1 activates StRBOH17 through phosphorylation, but also offer valuable genetic resources and important insights for molecular breeding of late blight-resistant potatoes. • A total of 18 members of the StRBOH gene family were identified in the potato genome. • StRBOH17 ( StRBOHA ) is potato leaf-specific RBOHs conferring late blight resistance. • There is a direct interaction between StBIK1 kinase and StRBOH17 protein.
Zhang et al. (Sun,) studied this question.