Project description:To gain an insight into molecular mechanisms underlying plant-microbe interactions gene expression changes in rice plants in response to a plant growth promoting rhizobacteria such as the Pseudomonas putida, root transcriptome analysis through microarray technology was performed from rice roots in response to P. putida RF3. Species of Pseudomonas are well known as biocontrol agents hence defense response and genes related to root exudation of phytochemicals were analysed in detail. For treatment of rice plants with P. putida, aseptically germinated rice seedlings from half strength MS medium were transferred to flasks containing Hoaglands’ nutrient solution, treated with P. putida and incubated for 48 hours in growth chamber in an orbital shaker. Gene expression changes in rice roots were then analyzed by microarray experiment. Untreated roots served as control. Data analysis revealed defense responsive genes to be upregulated with greater fold changes. In addition to defense response genes, few genes involved in secondary metabolism were also upregulated significantly. Validation of microarray data was performed using real time PCR for defense responsive genes (OsPBZ, OsPR101a, OsCHIA, etc). Detailed analysis of the differentially expressed genes reveal the role of P. putida RF3 in inducing systemic resistance in plants thereby immunizing the rice plants against future attacks by pests/pathogens. Our study enhances the current understanding on gene expression changes occurring during plant-microbe associations and thus demonstrates the potential of P. putida RF3 as a biocontrol agent.
Project description:Fairy rings are zones of stimulated grass growth by the interaction between the fungi and the plant. In the previous research, we reported the identification of the “fairy”, 2-azahypoxanthine (AHX), produced by the fairy ring-forming fungus and the mechanism of its growth-promoting activity using DNA microarray. We discovered AOH, a common metabolite of AHX in plants. We investigate expression profiling of rice seedlings treated with AHX or AOH for the mechanism of their growth-promoting activity.
Project description:Fairy rings are zones of stimulated grass growth by the interaction between the fungi and the plant. In the previous research, we reported the identification of the M-bM-^@M-^\fairyM-bM-^@M-^], 2-azahypoxanthine (AHX), produced by the fairy ring-forming fungus and the mechanism of its growth-promoting activity using DNA microarray. We discovered AOH, a common metabolite of AHX in plants. We investigate expression profiling of rice seedlings treated with AHX or AOH for the mechanism of their growth-promoting activity. Three-condition experiment, control vs. AHX-treated rice (50 and 200 mM) and AOH-treated rice (50 and 200 mM).
Project description:Nitrogen (N), a critical macronutrient for plant growth and development, is a major limiting factor in most agricultural systems. Microarray analyses have been conducted to investigate genome-wide gene expression in response to changes in N concentrations. Although RNA-Seq analysis can provide a more precise determination of transcript levels, it has not previously been employed to investigate the expression of N-starvation-induced genes. We constructed cDNA libraries from leaf sheaths and roots of rice plants grown under N-deficient or -sufficient conditions for 12 h. Sequencing the libraries resulted in identification of 33,782 annotated genes. A comparison of abundances revealed 1,650 transcripts that were differentially expressed (fold-changeââ¥â2) due to an N-deficiency. Among them, 1,158 were differentially expressed in the leaf sheaths (548 up-regulated and 610 down-regulated) and 492 in the roots (276 up, 216 down).
Project description:The purpose of this experiment was to study the effects of a bacterial ACC deaminase transgene in the roots and its impact on nickel tolerance of canola. ACC deaminase breaks down 1-aminocyclopropane-1-carboxylic acid, the biosynthetic precursor to the plant hormone ethylene, lowering ethylene levels and improving plant tolerance to stress. Ethylene evolved during plant stress is thought to causes senescence and cell death and worsen stress symptoms. Transgenic plants expressing ACC deaminase from the plant growth-promoting bacteria Pseudomonas putida UW4 are more tolerant to heavy metals in the soil and this expression study helps to illuminate the pathways responsible for this tolerance.
Project description:Fairy rings are zones of stimulated grass growth by the interaction between the fungi and the plant. In the previous research, we reported the identification of the “fairy”, ICAproduced by the fairy ring-forming fungus and the mechanism of its growth-inhibiting activity using DNA microarray. We invetigate expression profiling of rice seedlings treated with ICA for the mechanism of its growth-inhibiting activity.
Project description:Rice is one of the most important global food crops, and is also a model organism for cereal research 31 . Complete genome sequencing of rice, together with advances in transcriptomics and proteomics, has had a dramatic impact on plant growth and 5 breeding programs 32 . Genomic analysis of DNA methylation in rice has revealed methylation patterns associated with gene bodies and promoters, and the occurrence of high levels of DNA methylation in the centromeric domain 33 . A genome-wide investigation of acetylation in rice revealed that H3K9ac and H3K27ac are mainly enriched at transcription start sites associated with active transcription 34 . Furthermore, global proteome analysis has shown that phosphorylation and succinylation are involved in diverse cellular and metabolic processes 35, 36 . However, despite these considerable advances in our knowledge, additional large-scale analysis of the lysine acetylome in rice is expected to identify many more Kac sites and acetylated proteins in this improtant crop plant. In this study, affinity enrichment and high-resolution LC-MS/MS were used for large-scale analysis of the lysine acetylome in rice variety Nipponbare. In total, 1353 lysine acetylation sites were detected in 866 protein groups in rice seedlings. Proteomic analysis showed that Kac occurs in proteins involved in diverse biological processes with varied cellular functions and subcellular localization.
Project description:The experiment tested organ-specific responses of rice (Oryza sativa ssp. japonica) to cold stress with a special focus on phytohormonal regulation. Cold stress (5°C, 24 h) was applies on the whole plants, leaves or roots. The results showed distinct responses when cold stress was applied on leaves, relating to photosynthesis and sugar synthesis as well as specific changes in phytohormones. On the other hand, stress applied to roots was more similar to the stress on the whole plant indicating roots to be more important in cold stress responses. Acclimation by mild temperature (15°C, 12 h) highlighted changes which are connected even with lower temperature exposure or which are characteristic for untreated organs. Recovery (3 d) indicated ability of plants to restore growth which correlated between individual phytohormones and plant growth. The article connect transcriptome, hormonome, proteome and sugar analyses of rice cold-stress responses.
Project description:Gibberellins control a wide range of aspects of plant growth and development. Although a series of mutant of the signaling pathway has been identified, the global regulatory network underlying gibberellin signal transduction has not been revealed. To address this issue, we performed microarray analysis with rice gibberellin signaling mutants, gid1, gid2, slr, and the parental cultivar Taichung 65.