Exploiting plant immune "switches" for resistance engineering

Plant diseases, caused by various pathogens, pose a serious threat to sustainable agriculture. Plants have evolved a sophisticated immune system to detect and mount effective responses against pathogens. The plant immune system contains numerous programmable immune "switches" that safeguard plants against pathogens while minimizing energy consumption in the absence of pathogens. The cloning of disease-resistance (R) genes, along with the elucidation of the molecular mechanisms regulating these immune "switches", has provided resources and strategies for genetic engineering of novel disease resistance. This review focuses on the resistance engineering through the manipulation of immune "switches". It begins by summarizing recent advances in plant immunity, then explores the mechanisms behind plant immune "switches", and finally discusses potential strategies for engineering immune genes via these "switches". These strategies include engineering promoters to confer precise spatiotemporal regulation at the transcriptional level; engineering mRNA or its regulatory elements to facilitate specific and stable translation of R proteins at the post-transcriptional and translational levels; and engineering proteins at the post-translational level to broaden the pathogen-recognition spectrum of R proteins. Collectively, these strategies will accelerate the development of disease-resistant crop cultivars, thereby enhancing agricultural productivity and global food security.