Visualizing the Movement of Magnaporthe oryzae Effector Proteins in Rice Cells During Infection
During biotrophy, filamentous pathogens such as the rice blast fungus Magnaporthe oryzae deliver effector proteins into live host cells to facilitate colonization. We describe three complementary assays for visualizing M. oryzae effector translocation into the rice cytoplasm and cell-to-cell movement during infection. Our assays make use of live-cell confocal imaging of optically clear rice sheath cells infected with transgenic strains of M. oryzae that express the fluorescent protein-tagged effector known as PWL2. We highlight several important considerations for the analysis of effector translocation and movement dynamics during infection of host plants.
Key wordsBiotrophic interfacial complex Confocal imaging Effector proteins Fluorescent proteins Host translocation assay Live-cell imaging Magnaporthe oryzae Oryza sativa Plant–pathogen interactions Rice blast
We acknowledge the assistance of the Biomedical Microscopy Core at the University of Georgia with imaging using a Zeiss LSM 710 confocal microscope. This work was supported by the Agriculture and Food Research Initiative competitive grants program, Award number 2014-67013-21717 from the USDA National Institute of Food and Agriculture.
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