title: NB-LRR signaling induces translational repression of viral transcripts and the formation of RNA processing bodies through mechanisms differing from those activated by UV stress and RNAi.
abstract: Plant NB-LRR proteins confer resistance to multiple pathogens, including viruses. Although the recognition of viruses by NB-LRR proteins is highly specific, previous studies have suggested that NB-LRR activation results in a response that targets all viruses in the infected cell. Using an inducible system to activate NB-LRR defenses, we find that NB-LRR signaling does not result in the degradation of viral transcripts, but rather prevents them from associating with ribosomes and translating their genetic material. This indicates that defense against viruses involves the repression of viral RNA translation. This repression is specific to viral transcripts and does not involve a global shutdown of host cell translation. As a consequence of the repression of viral RNA translation, NB-LRR responses induce a dramatic increase in the biogenesis of RNA processing bodies (PBs). We demonstrate that other pathways that induce translational repression, such as UV irradiation and RNAi, also induce PBs. However, by investigating the phosphorylation status of eIF2α and by using suppressors of RNAi we show that the mechanisms leading to PB induction by NB-LRR signaling are different from these stimuli, thus defining a distinct type of translational control and anti-viral mechanism in plants.
authors.affiliation: Centre SÈVE, Département de Biologie, Université de Sherbrooke, 2500 Boulevard de l'Université, Sherbrooke J1K 2R1, QC, Canada.
authors.forename: Louis-Valentin
authors.initials: LV
authors.lastname: Meteignier
authors.affiliation: The Sainsbury Laboratory, Norwich Research Park, Norwich NR4 7UH, UK The Genome Analysis Centre & John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK.
authors.forename: Ji
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Centre SÈVE, Département de Biologie, Université de Sherbrooke, 2500 Boulevard de l'Université, Sherbrooke J1K 2R1, QC, Canada.
authors.forename: Mathias
authors.initials: M
authors.lastname: Cohen
authors.affiliation: Regional Centre for Biotechnology, 180, Udyog Vihar Phase I, Gurgaon-122016, India.
authors.forename: Saikat
authors.initials: S
authors.lastname: Bhattacharjee
authors.affiliation: Centre SÈVE, Département de Biologie, Université de Sherbrooke, 2500 Boulevard de l'Université, Sherbrooke J1K 2R1, QC, Canada.
authors.forename: Chantal
authors.initials: C
authors.lastname: Brosseau
authors.affiliation: Centre SÈVE, Département de Biologie, Université de Sherbrooke, 2500 Boulevard de l'Université, Sherbrooke J1K 2R1, QC, Canada.
authors.forename: Maria Goretty Caamal
authors.initials: MG
authors.lastname: Chan
authors.affiliation: The Sainsbury Laboratory, Norwich Research Park, Norwich NR4 7UH, UK.
authors.forename: Silke
authors.initials: S
authors.lastname: Robatzek
authors.affiliation: Centre SÈVE, Département de Biologie, Université de Sherbrooke, 2500 Boulevard de l'Université, Sherbrooke J1K 2R1, QC, Canada peter.moffett@usherbrooke.ca.
authors.forename: Peter
authors.initials: P
authors.lastname: Moffett
mesh_terms: D000070576:NLR Proteins / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000528:radiation effects; D017863:Potexvirus / Q000235:genetics; D014176:Protein Biosynthesis / Q000528:radiation effects*; D012315:RNA Caps / Q000378:metabolism; D034622:RNA Interference / Q000528:radiation effects*; D012323:RNA Processing, Post-Transcriptional / Q000528:radiation effects*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism; D015203:Reproducibility of Results; D015398:Signal Transduction; D013312:Stress, Physiological / Q000528:radiation effects*; D014026:Nicotiana / Q000235:genetics; D014466:Ultraviolet Rays
chemical_list: D000070576:NLR Proteins; D012315:RNA Caps; D012333:RNA, Messenger; D012367:RNA, Viral
keywords: DCP1; NB-LRR; P-bodies; RNA silencing; decapping; eIF2alpha; translation.