Transcriptome analysis of a progeny of somatic hybrids of cultivated rice (Oryza sativa L.) and wild rice (Oryza meyeriana L.) with high resistance to bacterial blight.

摘要

Previously, we successfully introduced the bacterial blight (BB) resistance trait from Oryza meyeriana into Oryza sativa using asymmetric somatic hybridization with O. meyeriana as the donor species. After years of breeding, a near-isogenic line named Y73 was generated with recurrent parent O. sativa L. ssp. japonica cv. Dalixiang, and it shows high resistance to a broad-spectrum BB pathogens Xanthomonas oryzae pv. oryzae. To provide insights into the high-resistance phenotype of these plants, we examined the transcriptome response in leaves of Y73 to BB infection 24 h postinoculation using Affymetrix Rice GeneChip microarrays. Microarray analysis revealed that there was little impact on the transcriptome of inoculated leaves compared with controls, with only 0.22% of genes that were differentially regulated. However, several interesting genes, including a NAC domain-containing protein, an elicitor-responsive protein, involved in ubiquitination, and a glycosyl transferase gene, two transcription factors (TFs) and two unknown genes were up-regulated more than five-fold. Genes for metabolic and cellular components, TFs and defence signalling, such as the mitogen-activated protein kinase cascade, were also significantly induced after Xoo infection. This study provides a genome-wide view of the initial reaction of rice (Y73) to Xoo infection and elucidates some of the genes that may play an important role in disease resistance.Digital Object Identifier http://dx.doi.org/10.1111/jph.12066