A novel pathway linking plasma membrane and chloroplasts is co-opted by pathogens to suppress salicylic acid-dependent defences

Medina-Puche, L.; Tan, H.; Dogra, V.; Wu, M.; Rosas-Diaz, T.; Wang, L.; Ding, X.; Zhang, D.; Fu, X.; Kim, C.; Lozano-Duran, R.

doi:10.1101/837955

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bioRxiv · 10.1101/837955

A novel pathway linking plasma membrane and chloroplasts is co-opted by pathogens to suppress salicylic acid-dependent defences

Medina-Puche, L.·Tan, H.·Dogra, V.·Wu, M.·Rosas-Diaz, T.·Wang, L.·Ding, X.·Zhang, D.·Fu, X.·Kim, C.·Lozano-Duran, R.

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Abstract

Chloroplasts are crucial players in the activation of defensive hormonal responses during plant-pathogen interactions. Here, we show that a plant virus-encoded protein re-localizes from the plasma membrane to chloroplasts upon triggering plant defence, interfering with the chloroplast-dependent activation of anti-viral salicylic acid (SA) biosynthesis. Strikingly, we have found that plant pathogens from different kingdoms seem to have convergently evolved to target chloroplasts and impair SA-dependent defences following an association with membranes, which is based on the co-existence of two subcellular targeting signals, an N-myristoylation site and a chloroplast transit peptide. This pattern is also present in plant proteins, at least one of which conversely activates SA defences from the chloroplast. Taken together, our results suggest that a pathway linking plasma membrane to chloroplasts and activating defence exists in plants, and that such pathway has been co-opted by plant pathogens during host-pathogen co-evolution to promote virulence through suppression of SA responses.

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Medina-Puche, L., Tan, H., Dogra, V., Wu, M., Rosas-Diaz, T., Wang, L., Ding, X., Zhang, D., Fu, X., Kim, C., Lozano-Duran, R.. 2019-11-12. A novel pathway linking plasma membrane and chloroplasts is co-opted by pathogens to suppress salicylic acid-dependent defences. https://doi.org/10.1101/837955

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