TY - JOUR
T1 - Phytotoxicity and innate immune responses induced by Nep1-like proteins
AU - Qutob, Dinah
AU - Kemmerling, Birgit
AU - Brunner, Frédéric
AU - Küfner, Isabell
AU - Engelhardt, Stefan
AU - Gust, Andrea A.
AU - Luberacki, Borries
AU - Seitz, Hanns Ulrich
AU - Stahl, Dietmar
AU - Rauhut, Thomas
AU - Glawischnig, Erich
AU - Schween, Gabriele
AU - Lacombe, Benoit
AU - Watanabe, Naohide
AU - Lam, Eric
AU - Schlichting, Rita
AU - Scheel, Dierk
AU - Nau, Katja
AU - Dodt, Gabriele
AU - Hubert, David
AU - Gijzen, Mark
AU - Nürnberger, Thorsten
PY - 2006/12
Y1 - 2006/12
N2 - We show that oomycete-derived Nep1 (for necrosis and ethylene-inducing peptide1)-like proteins (NLPs) trigger a comprehensive immune response in Arabidopsis thaliana, comprising posttranslational activation of mitogen-activated protein kinase activity, deposition of callose, production of nitric oxide, reactive oxygen intermediates, ethylene, and the phytoalexin camalexin, as well as cell death. Transcript profiling experiments revealed that NLPs trigger extensive reprogramming of the Arabidopsis transcriptome closely resembling that evoked by bacteria-derived flagellin. NLP-induced cell death is an active, light-dependent process requiring HSP90 but not caspase activity, salicylic acid, jasmonic acid, ethylene, or functional SGT1a/SGT1b. Studies on animal, yeast, moss, and plant cells revealed that sensitivity to NLPs is not a general characteristic of phospholipid bilayer systems but appears to be restricted to dicot plants. NLP-induced cell death does not require an intact plant cell wall, and ectopic expression of NLP in dicot plants resulted in cell death only when the protein was delivered to the apoplast. Our findings strongly suggest that NLP-induced necrosis requires interaction with a target site that is unique to the extracytoplasmic side of dicot plant plasma membranes. We propose that NLPs play dual roles in plant pathogen interactions as toxin-like virulence factors and as triggers of plant innate immune responses.
AB - We show that oomycete-derived Nep1 (for necrosis and ethylene-inducing peptide1)-like proteins (NLPs) trigger a comprehensive immune response in Arabidopsis thaliana, comprising posttranslational activation of mitogen-activated protein kinase activity, deposition of callose, production of nitric oxide, reactive oxygen intermediates, ethylene, and the phytoalexin camalexin, as well as cell death. Transcript profiling experiments revealed that NLPs trigger extensive reprogramming of the Arabidopsis transcriptome closely resembling that evoked by bacteria-derived flagellin. NLP-induced cell death is an active, light-dependent process requiring HSP90 but not caspase activity, salicylic acid, jasmonic acid, ethylene, or functional SGT1a/SGT1b. Studies on animal, yeast, moss, and plant cells revealed that sensitivity to NLPs is not a general characteristic of phospholipid bilayer systems but appears to be restricted to dicot plants. NLP-induced cell death does not require an intact plant cell wall, and ectopic expression of NLP in dicot plants resulted in cell death only when the protein was delivered to the apoplast. Our findings strongly suggest that NLP-induced necrosis requires interaction with a target site that is unique to the extracytoplasmic side of dicot plant plasma membranes. We propose that NLPs play dual roles in plant pathogen interactions as toxin-like virulence factors and as triggers of plant innate immune responses.
UR - http://www.scopus.com/inward/record.url?scp=33947515118&partnerID=8YFLogxK
U2 - 10.1105/tpc.106.044180
DO - 10.1105/tpc.106.044180
M3 - Article
C2 - 17194768
AN - SCOPUS:33947515118
SN - 1040-4651
VL - 18
SP - 3721
EP - 3744
JO - Plant Cell
JF - Plant Cell
IS - 12
ER -