Unser 10. Leibniz Plant Biochemistry Symposium am 7. und 8. Mai war ein großer Erfolg. Thematisch ging es in diesem Jahr um neue Methoden und Forschungsansätze der Naturstoffchemie. Die exzellenten Vorträge über Wirkstoffe…
Omanische Heilpflanze im Fokus der Phytochemie IPB-Wissenschaftler und Partner aus Dhofar haben jüngst die omanische Heilpflanze Terminalia dhofarica unter die phytochemische Lupe genommen. Die Pflanze ist reich an…
Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Stegmann, M.; Anderson, R. G.; Westphal, L.; Rosahl, S.; McDowell, J. M.; Trujillo, M.;The exocyst subunit Exo70B1 is involved in the immune response of Arabidopsis thaliana to different pathogens and cell deathPlant Signal Behav.8e27421(2013)DOI: 10.4161/psb.27421
Components of the vesicle trafficking machinery are central to the immune response in plants. The role of vesicle trafficking during pre-invasive penetration resistance has been well documented. However, emerging evidence also implicates vesicle trafficking in early immune signaling. Here we report that Exo70B1, a subunit of the exocyst complex which mediates early tethering during exocytosis is involved in resistance. We show that exo70B1 mutants display pathogen-specific immuno-compromised phenotypes. We also show that exo70B1 mutants display lesion-mimic cell death, which in combination with the reduced responsiveness to pathogen-associated molecular patterns (PAMPs) results in complex immunity-related phenotypes.
Publikation
Trujillo, M.; Ichimura, K.; Casais, C.; Shirasu, K.;Negative Regulation of PAMP-Triggered Immunity by an E3 Ubiquitin Ligase Triplet in ArabidopsisCurr. Biol.181396-1401(2008)DOI: 10.1016/j.cub.2008.07.085
The first line of active defense in plants is triggered by invariant microbial epitopes known as pathogen-associated molecular patterns (PAMPs). Perception of PAMPs by receptors activates a plethora of reactions ending in PAMP-triggered immunity (PTI), which contributes to broad-spectrum resistance 1, 2. Here, we report a homologous triplet of U-box type E3 ubiquitin ligases (PUBs), PUB22, PUB23, and PUB24 in Arabidopsis, that act as negative regulators of PTI in response to several distinct PAMPs. Expression of PUB22/PUB23/PUB24 was induced by PAMPs and infection by pathogens. The pub22/pub23/pub24 triple mutant displayed derepression and impaired downregulation of responses triggered by PAMPs. Immune responses including the oxidative burst, the MPK3 activity, and transcriptional activation of marker genes were increased and/or prolonged. Enhanced activation of PTI responses also resulted in increased resistance against bacterial and oomycete pathogens, which was accompanied by increased production of reactive oxygen species and cell death. Our data provide novel insights into the regulation of immunity in plants and links ubiquitination as a mechanism of negative regulation of PTI.