An oomycete effector co-opts a host RabGAP protein to remodel pathogen interface and subvert defense-related secretion

Yuen, E. L. H.; Tumtas, Y.; Chan, L. I.; Ibrahim, T.; Evangelisti, E.; Tulin, F.; Sklenar, J.; Menke, F.; Kamoun, S.; Bubeck, D.; Schornack, S.; Bozkurt, T. O.

doi:10.1101/2024.01.11.575225

bioRxiv · 10.1101/2024.01.11.575225

An oomycete effector co-opts a host RabGAP protein to remodel pathogen interface and subvert defense-related secretion

Yuen, E. L. H.·Tumtas, Y.·Chan, L. I.·Ibrahim, T.·Evangelisti, E.·Tulin, F.·Sklenar, J.·Menke, F.·Kamoun, S.·Bubeck, D.·Schornack, S.·Bozkurt, T. O.

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Abstract

Pathogens have evolved sophisticated mechanisms to manipulate host cell membrane dynamics, a crucial adaptation to survive in hostile environments shaped by innate immune responses. Plant- derived membrane interfaces, engulfing invasive hyphal projections of fungal and oomycete pathogens, are prominent junctures dictating infection outcomes. Understanding how pathogens transform these host-pathogen interfaces to their advantage remains a key biological question. Here, we identified a conserved effector, secreted by plant pathogenic oomycetes, that co-opts a host Rab GTPase-activating protein (RabGAP), TBC1D15L, to remodel the host-pathogen interface. The effector, PiE354, hijacks TBC1D15L as a susceptibility factor to usurp its GAP activity on Rab8a--a key Rab GTPase crucial for defense-related secretion. By hijacking TBC1D15L, PiE354 purges Rab8a from the plasma membrane, diverting Rab8a-mediated immune trafficking away from the pathogen interface. This mechanism signifies an uncanny evolutionary adaptation of a pathogen effector in co- opting a host regulatory component to subvert defense-related secretion, thereby providing unprecedented mechanistic insights into the reprogramming of host membrane dynamics by pathogens.

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Yuen, E. L. H., Tumtas, Y., Chan, L. I., Ibrahim, T., Evangelisti, E., Tulin, F., Sklenar, J., Menke, F., Kamoun, S., Bubeck, D., Schornack, S., Bozkurt, T. O.. 2024-01-15. An oomycete effector co-opts a host RabGAP protein to remodel pathogen interface and subvert defense-related secretion. https://doi.org/10.1101/2024.01.11.575225

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