Project description:Purpose:The goals of this study are to compare NGS-derived transcriptome profiling (RNA-seq) of different resistance to sheath blight in rice chromosome segment substitution lines
Project description:We carried out an RNA-seq based transcriptome study on two rice varieties, Cocodrie (CCDR; rice sheath blight susceptible) and MCR10277 (MCR; rice sheath blight resistant), to profile the time-series wide genome-scale transcriptional differences in response to sheath blight (SB), an infection caused by R. solanii (LR172) . Our approach is cross-referencing differentially expressed genes with significant variants of two phenotypically different varieties to validate known and discover novel variants and to further understand rice's physiological response to SB.
Project description:Pls4 is a gene encoding a β -ketoacyl carrier protein reductase (KAR), which is mainly involved in biological processes such as cell membrane formation. However，the role of pls4 in rice sheath blight remains unclear. Our preliminary studies showed that rice pls4 mutants were highly susceptive to sheath blight in early development stage, and insensitive in adulthood. To explore the role of this gene in the occurrence of rice sheath blight, we compared the transcriptome profiles of rice pls4 mutant and wild-type by RNA-seq. The results showed that, 2569 differentially expressed genes (DEGs), and down-regulated genes were significantly enriched in defense response related biological stress. The expression pattern significantly changed in genes related to pattern-triggered immunity (PTI) and effector-triggered immunity (ETI), which were the main two innate immunity pathways in plants. The chitinase-related genes were mainly down-regulated, while both the disease-related genes and the related genes of the WRKY gene family were significantly up-regulated. Furthermore, 467 genes had significantly alternative splicing (AS) events. Among them, intron retention (IR) affected the gene expression levels and functions in vitamin B6 (VB6) metabolism pathway, which was related to sheath blight. This suggested that IR played an important role in sheath blight resistance of mutant pls4. In conclusion, these studies suggested that pls4 might be involved in the biological stress process of sheath blight by DEGs and the fine-tuning of IR, which would provide a molecular basis for the study of rice sheath blight resistance.
Project description:An indica rice cultivar IET8585 (Ajaya), resists diverse races of the Xanthomonas oryzae pv oryzae (Xoo) 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. To further understand the mechanism of recessive and durable resistance response, two indica rice genotypes namely, i) IET8585 (Ajaya), a disease resistant indica veriety from India and ii) IR24, a bacterial leaf blight disease susceptible genotype were selected for this study. We used the 22K rice Oligoarray from Agilent technologies to study the transcript profile in the leaves of the two contrasting rice genotypes under inoculated and un-inoculated conditions during seedling stage. Keywords: Bacterial leaf blight disease resistance mechanism
Project description:Rice-Xanthomonas oryzae is an economically important pathosystem owing to the loss caused by bacterial blight disease. Understanding the moleulcar dynbamics that occur during rice-Xoo interaction is crucial for understanding disaease susceptible and resistance mechanisms. SM210, harbors the resistance alleles xa5, xa13, and Xa21 and is resistant against Xoo. Transcriptome analysis of Xoo-treated. SM210 and SM, its parent variety, indicated different pathways that are altered in these varieties after Xoo treatment.
Project description:Seedlings blight is one of the destructive diseases of rice, caused by the fungus Fusarium oxysporum, which impairs rice productions. Fluoro-substituted benzothiadiazole derivatives (FBT) and chitosan oligosaccharide (COS) are elicitors that can enhance plant resistance to pathogen infection. However, there is a lack of information regarding FBT and COS used as elicitors in rice seedlings blight. Therefore, the aim of this study was to evaluate the effect of FBT and COS treatments against rice seedling blight and elucidate the possible molecular mechanisms of the two elicitors for inducing resistance by proteomics. The results showed that FBT and COS significantly reduced the disease incidence and index, and improved the growth status of rice root caused by F. oxysporum. Biochemical analysis demonstrated that the two elicitors effectively enhanced activities of defense enzymes. Moreover, proteomic profiling analysis of rice root tissues disclosed more differentially expressed proteins in diterpenoid biosynthesis pathway induced by the two elicitors compared with other biological pathways, resulting in the accumulation of antimicrobial substance--momilactone. This study provided the basis of theory and application for FBT and COS used as rice elicitors against seedling blight on roots.
Project description:An indica rice cultivar IET8585 (Ajaya), resists diverse races of the Xanthomonas oryzae pv oryzae (Xoo) 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. To further understand the mechanism of recessive and durable resistance response, two indica rice genotypes namely, i) IET8585 (Ajaya), a disease resistant indica veriety from India and ii) IR24, a bacterial leaf blight disease susceptible genotype were selected for this study. We used the 22K rice Oligoarray from Agilent technologies to study the transcript profile in the leaves of the two contrasting rice genotypes under inoculated and un-inoculated conditions during seedling stage. Experiment Overall Design: We used Agilent rice gene chips (G4138A) to investigate the transcript level changes in rice leaf tissues during bacterial pathogen infection. We used two contrasting rice genotypes (IET8585 (Ajaya) blb resistant IR24 blb susceptible) differing in bacterial disease response. Plants were grown growth chambers and inoculated with bacterial pathogen on 18th DAS. Leaf sampling was done in both un-inoculated and inoculated plants at 3 time points. Two replications of microarray experiments were carried out by hybridizing the resistant samples against the susceptible samples.
Project description:We constructed seven small RNA libraries of Rhizoctonia solani AG1 IA and sequenced using Illumina GA II. The seven samples include mycelium cultured on PDA without rice incubated, 6 different stages at 10 hours (10h), 18h, 24h, 32h, 48h and 72h spanning the Rhizoctonia solani AG1 strains infection rice. We identified miRNA-like small RNAs (milRNAs) using MIREAP and mirdeep2. The milRNAs were used for further analysis of interactions between milRNA and mRNA that may involve in plant-infection.
