Balancing rice blast resistance and growth through suppression of the E3 ubiquitin ligase OsRING80

Abstract In crop plants, there is often a trade-off between growth and defense; modulating the balance is crucial for effective crop improvement. In rice (Oryza sativa), the DENSE AND ERECT PANICLE 2 (DEP2) mutant shows altered phenotypes such as a more vertical leaf angle, erect panicles, small and round grains, slightly lower thousand-grain weight, and dwarfism. Here, we determined that loss of DEP2 function enhances resistance to the rice blast fungus Magnaporthe oryzae. We established that DEP2 interacts with the E3 ubiquitin ligase OsRING80, which ubiquitinates DEP2 and promotes its degradation via the 26S proteasome pathway. Interestingly, the transcriptional level of OsRING80 was lower in dep2 mutant lines, suggesting feedback regulation of OsRING80 by DEP2. Remarkably, knocking out OsRING80 through CRISPR/Cas9-mediated gene editing resulted in greater resistance to M. oryzae without compromising plant growth. These findings reveal that OsRING80 plays a crucial role in balancing plant immunity and growth by targeting DEP2; they also provide a valuable candidate gene for developing improved rice cultivars with both disease resistance and optimal agronomic traits.