MoWhi2 Participates in Mitophagy and Pathogenesis by Modulating MoAti1 Protein Level in Magnaporthe Oryzae
Received date: 2025-12-03
Accepted date: 2026-03-26
Online published: 2026-06-15
Rice blast caused by the fungus Magnaporthe oryzae is one of the most devastating diseases affecting rice production. It was previously demonstrated that MoWHI2 is indispensable for mitophagy and full virulence in M. oryzae, yet the molecular mechanisms underlying its control of mitophagy remained unresolved. In this study, we found that MoWhi2 interacts with MoAti1, a SUN family protein that mediates mitophagy by recruiting the autophagy-associated protein MoAtg8. Phenotypic analysis showed that the defects of the ΔMowhi2/ΔMoati1 mutant in growth, conidiation, and pathogenicity were comparable to those of ΔMoati1, but more severe than those of ΔMowhi2. Furthermore, compared with the wild type, the ΔMowhi2/ΔMoati1 mutant exhibited a lower mitophagy level similar to that of the single deletion mutants ΔMowhi2 or ΔMoati1. In addition, deletion of MoWHI2 resulted in a decreased protein level of MoAti1, suggesting that MoWhi2 might regulate mitophagy by modulating the protein levels of MoAti1. Due to the absence of MoWhi2 orthologues in both rice and humans, we employed host-induced gene silencing (HIGS) targeting MoWHI2 in rice plants; the resultant transgenic rice lines displayed resistance to blast without agronomic penalties. Collectively, our data established that MoWhi2 regulates mitophagy and pathogenicity of M. oryzae by interacting with MoAti1, and can serve as a target for rice blast control strategies.
Key words： rice blast; pathogenesis; fungal disease; mitophagy; Whi2; host-induced gene silencing
Zhang Ying , Shi Huanbin , Meng Shuai , Wen Hui , Chen Ya , Liu Li , Kou Yanjun . MoWhi2 Participates in Mitophagy and Pathogenesis by Modulating MoAti1 Protein Level in Magnaporthe Oryzae[J]. Rice Science, 2026 , 33(4) : 545 -558 . DOI: 10.1016/j.rsci.2026.03.009
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