CLP responses in plants: Arabidopsis, tomato

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CLP responses in plants Arabidopsis, tomato
Priming Conditioning of the plant to react
faster/stronger to biotic or abiotic stress.
Plant Cell 17 987-999 (2005) PNAS 103
5602-5607 (2006) MPMI 19 1062-1071 (2006)
P. fluorescens-induced priming potentiated
expression pattern of defense-related gene LOX2.
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CLP responses in plants Arabidopsis, tomato
Priming Effective against a broad spectrum of
biotic and abiotic stresses.
oomyc.
bacteria
fungi
virus
insects
Pieris rapae
Spodoptera exigua
Fusarium oxysporum
Botrytis cinerea
Alternaria brassicicola
Pseudomonas syringae
Xanthomonas campestris
Turnip crinkle virus
Hyaloperonospora parasitica
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• CLP responses in plants Arabidopsis, tomato
• Research question
• How do microbial CLPs activate the plants
  immune response without affecting plant growth
  and yield?
• Research goals
• Identify Arabidopsis/tomato genes directly
  activated by CLPs (probably small number if any)
• Identify Arabidopsis/tomato genes that are
  primed by CLPs and show boosted expression
  pattern upon biotic or abiotic stress conditions.
• Analyze promoters of primed genes to identify
  candidate master regulators (transcription
  factors) that are essential for CLP-mediated
  priming.
• Investigate importance of identified master
  regulators in CLP-induced resistance by knock-out
  mutant analysis.
• Identify molecular markers for CLP-primed state

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CLP responses in plants Arabidopsis, tomato

• Methods
• Whole-genome microarray analysis (Affymetrix
  GeneChips) of CLP-treated Arabidopsis before and
  after infection with different pathogens or
  treatment with abiotic stress (drought/salt).
• Bioinformatics approach to identify regulatory
  promoter elements
• Knock-out mutant analysis to validate importance
  of identified candidate genes, using established
  bioassays with different pathogens (e.g.
  Phytophthora, Botrytis) and abiotic stresses
  (drought, salt, temperature).
• Utilization/deliverables
• This part of the project aims to gain insight in
  the molecular mechanism underlying CLP activation
  of enhanced stress resistance/tolerance.
• The whole-genome approach will yield important
  information on the set of CLP-primed genes in
  plants (markers).
• Robust sets of marker genes can be used to test
  the capacity of CLP derivatives to prime plants
  for enhanced vigour, such as triggered upon seed
  priming.
• Idenfification of master regulators of
  CLP-induced priming.

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CLP responses in plants Arabidopsis, tomato

• Expertise Plant-Microbe Interactions group,
  Utrecht University
• Corné Pieterse
• Exploiting Arabidopsis as a model to study the
  innate immune response in plants (molecular
  genetic toolbox of Arabidopsis).
• Resistance bioassays with large number of
  different microbial pathogens on Arabidopsis (and
  other plant species).
• Whole-genome expression profiling (Affymetrix
  Arabidopsis GeneChips)
• Kinome profiling (PepChips).
• Plant defense signaling during Pseudomonas
  fluorescens-mediated induced systemic resistance
  (ISR)