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bioRxiv · 10.1101/287508

Pseudomonas syringae evades phagocytosis in animal cells through type III effector-mediated inhibition of the LIM kinase-cofilin system

Ryu, C.-M.·Yoon, S.-J.·Lee, S.·Kim, J.-S.·Lee, S.-H.·Choi, S.·Min, J.-K.·Choi, I.·Park, Y.-J.
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Abstract

Certain animal and plant pathogenic bacteria have developed virulence factors (including effector proteins) that enable them to overcome host immunity. A plant pathogen, Pseudomonas syringae pv. tomato (Pto), secretes a large repertoire of effectors into plant cells via a type III secretory apparatus, thereby suppressing plant immunity. Here, we show that exposure to Pto caused sepsis in mice. Surprisingly, the effector HopQ1 disrupted phagocytosis by inhibiting actin rearrangement via a direct interaction with the LIM domain of the animal target protein LIM kinase, a key regulator of actin polymerization. The results provide new insights into cross-kingdom pathogenicity of bacteria. The current studies demonstrate that certain plant pathogenic bacteria such as Pto can be fatal in animals due to cross-kingdom host immune suppression.

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Ryu, C.-M., Yoon, S.-J., Lee, S., Kim, J.-S., Lee, S.-H., Choi, S., Min, J.-K., Choi, I., Park, Y.-J.. 2018-03-26. Pseudomonas syringae evades phagocytosis in animal cells through type III effector-mediated inhibition of the LIM kinase-cofilin system. https://doi.org/10.1101/287508

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