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W E Durrant

Publications and source records attributed to W E Durrant.

2 recordsLinked to original sources
PubMed2004

Systemic acquired resistance.

Systemic acquired resistance (SAR) is a mechanism of induced defense that confers long-lasting protection against a broad spectrum of microorganisms. SAR requires the signal molecule salicylic acid (SA) and is associated with accumulation of pathogenesis-related proteins, which are thought to contribute to resistance. Much progress has been made recently in elucidating the mechanism of SAR. Using the model plant Arabidopsis, it was discovered that the isochorismate pathway is the major source of SA during SAR. In response to SA, the positive regulator protein NPR1 moves to the nucleus where it interacts with TGA transcription factors to induce defense gene expression, thus activating SAR. Exciting new data suggest that the mobile signal for SAR might be a lipid molecule. We discuss the molecular and genetic data that have contributed to our understanding of SAR and present a model describing the sequence of events leading from initial infection to the induction of defense genes.

Arabidopsis↗
PubMed2000

cDNA-AFLP reveals a striking overlap in race-specific resistance and wound response gene expression profiles.

The tomato Cf-9 gene confers resistance to races of the fungal pathogen Cladosporium fulvum expressing the Avr9 gene. cDNA amplified fragment length polymorphism analysis was used to display transcripts whose expression is rapidly altered during the Avr9- and Cf-9-mediated defense response in tobacco cell cultures. Diphenyleneiodonium was used to abolish the production of active oxygen species during gene induction. Of 30,000 fragments inspected, 290 showed altered abundance, of which 263 were induced independently of active oxygen species. cDNA clones were obtained for 13 ACRE (for Avr9/Cf-9 rapidly elicited) genes. ACRE gene induction occurred in the presence of cycloheximide. Avr9 induced ACRE gene expression in leaves. Surprisingly, ACRE genes were also rapidly but transiently induced in leaves in response to other stresses. The amino acid sequences of some ACRE proteins are homologous to sequences of known proteins such as ethylene response element binding protein transcription factors, the N resistance protein, a calcium binding protein, 13-lipoxygenase, and a RING-H2 zinc finger protein. Rapid induction of ACRE genes suggests that they play a pivotal role during plant defense responses.

Ascomycota↗