title: Transcriptional profiling of indica rice cultivar IET8585 (Ajaya) infected with bacterial leaf blight pathogen Xanthomonas oryzae pv oryzae.
abstract: An indica rice cultivar IET8585 (Ajaya) resists diverse races of the Xanthomonas oryzae pv oryzae pathogen attack, and is often cultivated as bacterial leaf blight (blb) resistant check in India. Earlier we reported a recessive blb resistance gene mapped to the long arm of chromosome 5 in IET8585. Recessive gene-mediated blb resistance mechanism is not yet clearly understood. Here we analyzed the transcriptional profile of the blb infected resistant cultivar by rice 22K oligo array. Microarray analysis revealed differential expression of numerous genes at both early (6 h) and late (120 h) stages of infection in the resistant IET8585 cultivar over the susceptible IR24. Some of the differential gene expressions were validated by both RT-PCR and Western blot analysis. Higher expression of ethylene response element binding protein (EREBP) transcription factor along with lower expression of alcohol dehydrogenase gene and reactive oxygen species (ROS) scavenging system may be responsible for hypersensitive cell death in the resistant cultivar upon bacterial infection. Induction of glutathione-mediated detoxification and flavonoid biosynthetic pathways along with up-regulation of defense genes during infection may inhibit pathogen spread in the host tissues. In light of this and previous studies a mechanism of recessive gene-mediated bacterial blight resistance in indica rice is discussed.
authors.affiliation: Plant Genome Research Unit, National Institute of Agrobiological Sciences, 2-1-2 Kannon-dai, Tsukuba 305-8602, Ibaraki, Japan. kottapallisri@gmail.com
authors.forename: Kameswara Rao
authors.initials: KR
authors.lastname: Kottapalli
authors.forename: Randeep
authors.initials: R
authors.lastname: Rakwal
authors.forename: Kouji
authors.initials: K
authors.lastname: Satoh
authors.forename: Junko
authors.initials: J
authors.lastname: Shibato
authors.forename: Pratibha
authors.initials: P
authors.lastname: Kottapalli
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Iwahashi
authors.forename: Shoshi
authors.initials: S
authors.lastname: Kikuchi
mesh_terms: D015153:Blotting, Western; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D005838:Genotype; D020411:Oligonucleotide Array Sequence Analysis; D012275:Oryza / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology; D010641:Phenotype; D018515:Plant Leaves / Q000235:genetics* / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D014974:Xanthomonas / Q000502:physiology*
chemical_list: D010940:Plant Proteins; D017382:Reactive Oxygen Species