Spatial Regulation of Defense-Related Genes Revealed by Expression Analysis using Dissected Tissues of Rice Leaves Inoculated with Magnaporthe oryzae

Spatial Regulation of Defense- Related Genes Revealed by Expression Analysis using Dissected Tissues of Rice Leaves Inoculated with Magnaporthe oryzae

Gene expression profiles in response to inoculation with Magnaporthe oryzae at infected and adjacent cells obtained by microarray coupled with laser microdissection (LMD) were compared with results of microarray expression profiling using RNAs from pathogen infected whole leaves (WL). Genes whose expression was up-regulated following inoculation with the fungus were classified into two categories: group A indicates those whose increased expression was detected both in LMD- and WLmicroarrays, while group B indicates genes of which the expression was detected at significantly higher levels in WL-microarray than LMD-microarray. Interestingly, genes encoding enzymes for the biosynthesis of diterpenoid phytoalexins were exclusively found in group A, while pathogenesis-related (PR) genes were found in both groups A and B.