ABSTRACT
Fungal pathogens deliver effector proteins into living plant cells to suppress plant immunity and control plant processes that are needed for infection. During plant infection, the devastating rice blast fungus, Magnaporthe oryzae, forms the specialized biotrophic interfacial complex (BIC), which is essential for effector translocation. Cytoplasmic effectors are first focally secreted into BICs, and subsequently packaged into dynamic membranous effector compartments (MECs), then translocated via clathrin-mediated endocytosis (CME) into the host cytoplasm. This study demonstrates that clathrin-heavy chain inhibitors endosidin-9 (ES9) and endosidin-9–17 (ES9–17) blocked the internalization of the fluorescently labeled effectors Bas1 and Pwl2 in rice cells, leading to swollen BICs lacking MECs. In contrast, ES9–17 treatment had no impact on the localization pattern of the apoplastic effector Bas4. This study provides further evidence that cytoplasmic effector translocation occurs by CME in BICs, suggesting a potential role for M. oryzae effectors in co-opting plant endocytosis.
Acknowledgments
The authors are grateful to Dr. Frantisek Baluska for kindly inviting this communication. This project was supported by Louisiana State University Agricultural Center Hatch project #LAB94477, and from Louisiana Board of Regents grant #LEQSF(2022-24)-RD-A-01.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Supplementary material
Supplemental data for this article can be accessed online at https://doi.org/10.1080/15592324.2024.2350869