Project description:The transcription factor Mac1 is a key regulator of copper homeostasis and controls the transcriptional response to copper-limiting conditions in fungi. Expression analyses performed in the soil-borne plant pathogen Fusarium oxysporum revealed that almost all copper starvation-induced genes are downregulated in the absence of the regulator Mac1. The aim of this ChIP-seq analysis is to elucidate which of these genes are direct targets of Mac1.
Project description:Phytophthora cinnamomi is a devastating soil-borne oomycete with a very broad host range however there remains a major gap in the understanding of plant resistance responses to the pathogen, furthermore, necrotrophic plant-pathogen interactions, particularly those of root pathogens, remain poorly understood. Zea mays exhibits non-host resistance to the pathogen and has been well characterised as a model species. Using the maize Affymetrix GeneChip array we conducted genome-wide gene expression profiling to elucidate the defence genes and pathways which are induced in the root tissue of a resistant plant species to the pathogen.
Project description:We addressed the question how the interaction between the beneficial root endophyte Serendipita vermifera (Sv) and the pathogen Bipolaris sorokiniana (Bs) affects fungal behavior and determines barley host responses using a gnotobiotic natural soil-based split-root system for phenotypic and transcriptional analyses.
Project description:Purpose: Investigate genes associated with Phn7.1, a major QTL influencing partial resistance to the soil-borne pathogen Phytophthora nicotianae in tobacco. Methods: Resistant and susceptible tobacco near isogenic lines with and without Phn7.1 QTL were subjected to the inoculation with Phytophthora nicotianae suspension and suspension buffer without pathogen as control followed by sample collection at 42 hour past inoculation for RNA-seq analysis. Results: Revealed gene expression profiles associated disease resistance and susceptiblilty.
Project description:Bacterial wilt caused by Ralstonia solanacearum is a lethal, soil-borne disease of tomato. Control of the disease with chemicals and crop rotation is insufficient, because the pathogen is particularly well adapted for surviving in the soil and rhizosphere. Therefore, cultivar resistance is the most effective means for controlling bacterial wilt, but the molecular mechanisms of resistance responses remain unclear. We used microarrays to obtain the characteristics of the gene expression changes that are induced by R. solanacearum infection in resistant cultivar LS-89 and susceptible cultivar Ponderosa.
Project description:Identifying the genetic basis for natural selection is a fundamental research goal, and particularly significant for soil fungi because of their central role in ecosystem functioning. Here, we identify rapid evolutionary processes in the plant root colonizing insect pathogen Metarhizium robertsii. While adapting to a new soil community, expression of TATA box containing cell wall and stress response genes evolved at an accelerated rate, whereas virulence determinants, transposons and chromosome structure were unaltered. The survival of diversified field isolates was increased, confirming that the mutations were adaptive, and we further show that large populations of Metarhizium are principally maintained by associations with plant roots rather than insect populations. These results provide a mechanistic basis for understanding mutational and selective effects on soil microbes.
Project description:Plants growing in soil are challenged by multiple biotic (e.g. pathogens) and abiotic (e.g. heavy metals) stressors. Stress resistance is a key determinant for plants to thrive in the environment. Resistance to pathogens requires innate immunity , whereas tolerance to metal ions is accomplished by mechanisms such as complexation and compartmentation. Some transition metals can enhance plant’s defense against pathogens4,5, but the mechanism remains unclear. Here, we show that an Arabidopsis head-to-head gene pair of intracellular nucleotide-binding leucine-rich repeat (NLR) receptors antagonistically control transition metal-triggered immunity. One NLR, STM2 directly perceives transition metal ions, such as Cd2+, Cu2+ and Zn2+, as a ligand to activate its NAD+ hydrolytic activity and immune responses, triggering enhanced resistance to the soil-borne bacterial wilt pathogen Ralstonia solanacearum. The other NLR, STM1 suppresses STM2 to protect plants from transition metal-triggered immunity and growth inhibition in the presence of excess metals. STM1 also dampens resistance to the pathogen. Our study defines an NLR activated by transition metals and reveals a trade-off between resistance to pathogens and tolerance to transition metals that are pervasive in soil.
Project description:Plants growing in soil are challenged by multiple biotic (e.g. pathogens) and abiotic (e.g. heavy metals) stressors. Stress resistance is a key determinant for plants to thrive in the environment. Resistance to pathogens requires innate immunity 1, whereas tolerance to metal ions is accomplished by mechanisms such as complexation and compartmentation2,3. Some transition metals can enhance plant’s defense against pathogens4,5, but the mechanism remains unclear. Here, we show that an Arabidopsis head-to-head gene pair of intracellular nucleotide-binding leucine-rich repeat (NLR) receptors antagonistically control transition metal-triggered immunity. One NLR, STM2 directly perceives transition metal ions, such as Cd2+, Cu2+ and Zn2+, as a ligand to activate its NAD+ hydrolytic activity and immune responses, triggering enhanced resistance to the soil-borne bacterial wilt pathogen Ralstonia solanacearum. The other NLR, STM1 suppresses STM2 to protect plants from transition metal-triggered immunity and growth inhibition in the presence of excess metals. STM1 also dampens resistance to the pathogen. Our study defines an NLR activated by transition metals and reveals a trade-off between resistance to pathogens and tolerance to transition metals that are pervasive in soil.