Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2003-8-27
pubmed:abstractText
Pseudomonas syringae pv. tomato DC3000 is a pathogen of tomato and Arabidopsis that injects virulence effector proteins into host cells via a type III secretion system (TTSS). TTSS-deficient mutants have a Hrp- phenotype, that is, they cannot elicit the hypersensitive response (HR) in non-host plants or pathogenesis in host plants. Mutations in effector genes typically have weak virulence phenotypes (apparently due to redundancy), but deletion of six open reading frames (ORF) in the DC3000 conserved effector locus (CEL) reduces parasitic growth and abolishes disease symptoms without affecting function of the TTSS. The inability of the DeltaCEL mutant to cause disease symptoms in tomato was restored by a clone expressing two of the six ORF that had been deleted: CEL ORF3 (HopPtoM) and ORF4 (ShcM). A DeltahopPtoM::nptII mutant was constructed and found to grow like the wild type in tomato but to be strongly reduced in its production of necrotic lesion symptoms. HopPtoM expression in DC3000 was activated by the HrpL alternative sigma factor, and the protein was secreted by the Hrp TTSS in culture and translocated into Arabidopsis cells by the Hrp TTSS during infection. Secretion and translocation were dependent on ShcM, which was neither secreted nor translocated but, like typical TTSS chaperones, could be shown to interact with HopPtoM, its cognate effector, in yeast two-hybrid experiments. Thus, HopPtoM is a type III effector that, among known plant pathogen effectors, is unusual in making a major contribution to the elicitation of lesion symptoms but not growth in host tomato leaves.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
49
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1239-51
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:12940984-Bacterial Proteins, pubmed-meshheading:12940984-Blotting, Western, pubmed-meshheading:12940984-Colony Count, Microbial, pubmed-meshheading:12940984-Culture Media, pubmed-meshheading:12940984-DNA-Binding Proteins, pubmed-meshheading:12940984-Gene Deletion, pubmed-meshheading:12940984-Gene Expression Regulation, pubmed-meshheading:12940984-Genes, Bacterial, pubmed-meshheading:12940984-Genes, Reporter, pubmed-meshheading:12940984-Lycopersicon esculentum, pubmed-meshheading:12940984-Molecular Chaperones, pubmed-meshheading:12940984-Open Reading Frames, pubmed-meshheading:12940984-Plant Diseases, pubmed-meshheading:12940984-Plant Leaves, pubmed-meshheading:12940984-Protein Interaction Mapping, pubmed-meshheading:12940984-Protein Transport, pubmed-meshheading:12940984-Pseudomonas, pubmed-meshheading:12940984-Sigma Factor, pubmed-meshheading:12940984-Two-Hybrid System Techniques
pubmed:year
2003
pubmed:articleTitle
Pseudomonas syringae pv. tomato DC3000 HopPtoM (CEL ORF3) is important for lesion formation but not growth in tomato and is secreted and translocated by the Hrp type III secretion system in a chaperone-dependent manner.
pubmed:affiliation
Department of Plant Pathology, Cornell University, Ithaca, NY 14853, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.