Submitted to: Korean-Japan Joint Seminar Collaborative Researches on Biological Science
Publication Type: Abstract Only
Publication Acceptance Date: October 5, 2005
Publication Date: October 11, 2005
Citation: Clough, S.J. 2005. DNA microarray analysis of soybean-microbe interactions [abstract]. Korean-Japan Joint Seminar Collaborative Researches on Biological Science. p. 2. Technical Abstract: Microarrays of spotted PCR amplified cDNA, or gene-specific oligomers, allow one to screen for differential gene expression by comparing mRNA abundance from different tissues. We are using soybean microarrays to screen for gene expression affected by plant association with pathogenic and symbiotic microbes. With a focus on the hypersensitive defense reaction (HR) induced in leaves as a base study into soybean defense against pathogens, we screened approximately 27,000 cDNA for expression in leaves infiltrated with Pseudomonas syringae at 2, 8, and 24 hours post inoculation (hpi). ANOVA analysis identified that approximately 4,000 genes were significantly differentially expressed during the experiment. Gene annotation suggested that many of the defense reactions were typical of defense responses observed in other plants, such as activation of heat shock proteins, calcium signalling, DNA/RNA associated proteins, and enzymes catalyzing secondary metabolites. In addition, we also observed a strong down-regulation of nuclear-encoded chloroplast genes suggesting that photosynthesis is rapidly being disrupted during the HR. Photosynthetic measurements were consistent with an HR-specific reduction in photosystem II operating efficiency (Phi PSII) that became apparent within 8 hpi.