title: Signals for local and systemic responses of plants to pathogen attack.
abstract: Activation of plant defences following recognition of pathogen attack involves complex reiterative signal networks with extensive signal amplification and cross-talk. The results of two approaches that have been taken to analyse signalling in plant-microbe interactions are discussed here. Activation tagging with T-DNA harbouring multiple 35S enhancer elements was employed as a gain-of-function approach to dissect signalling related to bacterial pathogen resistance in Arabidopsis thaliana. From a screen of approximately 5000 activation tagged lines, one line was identified as harbouring a T-DNA leading to over-expression of an apoplastic aspartic protease (CDR-1), that resulted in resistance to normally virulent Pseudomonas syringae. The second approach was to screen for loss-of-function mutants in T-DNA tagged populations. From a screen of 11 000 lines, one line, defective in induced resistance-1 (dir-1) lost resistance to normally avirulent P. syringae. Models for action of the products of the CDR-1 and DIR-1 genes suggest involvement of peptide and lipid signals in systemic disease resistance responses in A. thaliana.
authors.affiliation: Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Suzuki
authors.forename: Yiji
authors.initials: Y
authors.lastname: Xia
authors.forename: Robin
authors.initials: R
authors.lastname: Cameron
authors.forename: Gail
authors.initials: G
authors.lastname: Shadle
authors.forename: Jack
authors.initials: J
authors.lastname: Blount
authors.forename: Chris
authors.initials: C
authors.lastname: Lamb
authors.forename: Richard A
authors.initials: RA
authors.lastname: Dixon
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000382:microbiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000302:isolation & purification; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers; D004269:DNA, Bacterial / Q000302:isolation & purification*; D004277:DNA, Single-Stranded / Q000302:isolation & purification; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D016297:Mutagenesis, Site-Directed; D010935:Plant Diseases; D010937:Plant Growth Regulators / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D029702:Schizosaccharomyces pombe Proteins
chemical_list: D029681:Arabidopsis Proteins; D017931:DNA Primers; D004269:DNA, Bacterial; D004277:DNA, Single-Stranded; D010937:Plant Growth Regulators; D029702:Schizosaccharomyces pombe Proteins; C036483:T-DNA; C080364:cdr1 protein, S pombe; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases