PT  - JOURNAL ARTICLE
AU  - Laura Medina-Puche
AU  - Huang Tan
AU  - Vivek Dogra
AU  - Mengshi Wu
AU  - Tabata Rosas-Diaz
AU  - Liping Wang
AU  - Xue Ding
AU  - Dan Zhang
AU  - Xing Fu
AU  - Chanhong Kim
AU  - Rosa Lozano-Duran
TI  - A novel pathway linking plasma membrane and chloroplasts is co-opted by pathogens to suppress salicylic acid-dependent defences
AID  - 10.1101/837955
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 837955
4099  - http://biorxiv.org/content/early/2019/11/12/837955.short
4100  - http://biorxiv.org/content/early/2019/11/12/837955.full
AB  - 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.