During plant cell invasion, the oomycete Phytophthora infestans remains enveloped by host-derived membranes whose functional properties are poorly understood. P. infestans secretes a myriad of effector proteins through these interfaces for plant colonization. Recently we showed that the effector protein PexRD54 reprograms host-selective autophagy by antagonising antimicrobial-autophagy receptor Joka2/NBR1 for ATG8CL binding (Dagdas, 2016). Here, we show that during infection, ATG8CL/Joka2 labelled defense-related autophagosomes are diverted toward the perimicrobial host membrane to restrict pathogen growth. PexRD54 also localizes to autophagosomes across the perimicrobial membrane, consistent with the view that the pathogen remodels host-microbe interface by co-opting the host autophagy machinery. Furthermore, we show that the host-pathogen interface is a hotspot for autophagosome biogenesis. Notably, overexpression of the early autophagosome biogenesis protein ATG9 enhances plant immunity. Our results implicate selective autophagy in polarized immune responses of plants and point to more complex functions for autophagy than the widely known degradative roles.
All data generated or analysed during this study are included in the manuscript and supporting files.
- Yasin F Dagdas
- Khaoula Belhaj
- Sophien Kamoun
- Tolga O Bozkurt
- Pooja Pandey
- Yasin Tumtas
- Nattapong Sanguankiattichai
- Cian Duggan
- Alexandre Y Leary
- Maria Segretin
- Mauricio Contreras
- Zachary Savage
- Tolga O Bozkurt
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Jian-Min Zhou, Chinese Academy of Sciences, China
© 2018, Dagdas et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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