Plant & Animal Genomes XI Conference

January 11-15, 2003
Town & Country Convention Center
San Diego, CA

Poster: Genome Sequencing & ESTs
            

IDENTIFICATION OF GENES SPECIFICALLY EXPRESSED IN PLANT-MICROBE INTERACTIONS

Department of Agronomy and Plant Genetics, University of Minnesota, 411 Borlaug Hall, 1991 Upper Buford Circle, St. Paul, MN, 55108, USA

Cloning of resistance genes, mutant analysis and RNA profiling have shown that similarities in resistance genes, signaling and response gene expression exist amongst different plant-microbe interactions. A set of 70 plant genes that were only found as expressed sequence tags (ESTs) in at least two different plant-microbe interactions was identified. Approximately 25,000 ESTs, from barley and wheat infected with Fusarium graminearum and barley infected with Blumeria graminis f.sp. hordei, were compared to all ESTs in dbEST, which includes over 134,000 ESTs from plant-microbe interactions, using the BLASTN algorithm (P*10-5). Thirteen of these genes were expressed in three plant-microbe interactions and one, an ATP-dependent copper transporter, was expressed in four different interactions. A gene encoding the resistance gene Xa21 and one encoding lipoxygenase were the only genes with functions related to response to infection, although 4 genes encoding receptor kinases could be resistance gene analogs. Almost 56% (39/70) of the genes encode proteins with unknown functions. Most of the genes (67/70) were identified from interactions between a cereal host and a fungal pathogen. These genes were expressed in race-specific and in quantitative resistant interactions with biotrophic and necrotrophic pathogens. Only three genes, the copper transporter, a hypothetical protein and a homolog to the Arabidopsis gene AT5g14760/T9L3_60, were expressed in plant-fungal and in symbiotic plant-bacterial interactions. Our analysis indicates that there may be a core set of pathways that are universally activated in all plant-microbe interactions.