Project description:Endophytic fungi are root-inhabiting fungi that can promote plant growth in a variety of ways. They can directly stimulate plant growth by producing phytohormones, such as auxin and gibberellins. They can also indirectly promote plant growth by helping plants to acquire nutrients, such as nitrogen and phosphorus, and by protecting plants from pests and pathogens.In this study, we used a proteomic approach to identify the proteins that are expressed in rice plants after they are treated with endophytic fungi. We found that the treatment with endophytic fungi resulted in the expression of a number of proteins involved in plant growth, nutrient acquisition, and defense. These results suggest that endophytic fungi can promote plant growth and improve plant resilience to stress.
Project description:Endophytic fungi are fungi that live inside the roots of plants. They can promote plant growth through a variety of direct and indirect mechanisms. Direct mechanisms include the production of phytohormones, such as auxin and gibberellins, which can stimulate plant growth. Endophytic fungi can also fix nitrogen, solubilize phosphate, and produce siderophores, which are compounds that chelate iron and make it available to plants. In addition, some endophytic fungi produce antimicrobial metabolites that can protect plants from pests and pathogens. Indirect mechanisms include the induction of systemic resistance, which is a plant's ability to defend itself against pests and pathogens. Endophytic fungi can also help plants to tolerate abiotic stresses, such as drought, salinity, and heavy metals. In this study, we used a proteomic approach to identify the proteins that are expressed in rice plants after they are treated with endophytic fungi. We found that the treatment with endophytic fungi resulted in the expression of a number of proteins involved in plant growth, stress response, and defense. These results suggest that endophytic fungi can promote plant growth and improve plant resilience to stress.
Project description:Plants balance their conflicting requirements for growth and stress tolerance via sophisticated pathways and unique genes that control responses to the external environment. We have identified a novel plant-specific gene, COST1(Constitutively Stressed 1), that affects plant growth and negatively regulates drought resistance by manipulating the autophagy pathway. An Arabidopsis cost1 mutant has decreased growth and increased drought tolerance, together with constitutive autophagy and increased expression of drought-response genes. The COST1 protein is degraded upon plant dehydration, and this degradation is blocked by treatment with inhibitors of the 26S proteasome or autophagy pathways. The cost1 mutant drought resistance is dependent on an active autophagy pathway, indicating that COST1 acts through manipulation of autophagy. COST1 co-localizes to autophagosomes with the autophagosome marker ATG8e and the autophagy adaptor NBR1, and physically interacts with ATG8e, indicating a pivotal role in direct regulation of autophagy. We propose a model in which COST1 represses autophagy under optimal conditions, thus allowing plant growth. During drought, COST1 is degraded, enabling activation of autophagy and suppressing growth to enhance drought tolerance.
Project description:Temperature passively affects many biological processes. It is therefore challenging to study dedicated temperature signalling pathways orchestrating plant thermomorphogenesis; a suite of elongation growth-based adaptations that enhance leaf cooling capacity. Following a chemical genetics approach, we screened a chemical library for compounds that restored abolished hypocotyl elongation in the pif4-2 deficient mutant background in the model plant Arabidopsis thaliana. The small aromatic compound ‘Heatin' (N'-[(2-hydroxy-1-naphthyl)methylene]-2-(1-naphthylamino)propanohydrazide), with 1-aminomethyl-2-naphthol, as minimal active moiety, was isolated as potent enhancer of elongation growth. Here we assessed the transcriptomic changes induced by the compound, by supplementing the MS-agar growth medium with Heatin compared to DMSO solvent, in whole seedlings of the Col-0 wild type background in control (22oC) and high ambient temperature conditions (27oC).
Project description:Conidial germination marks the beginning of the fungal life cycle, and understanding the genes associated with conidial germination provides insights into fungal pathogenicity and host interactions. Here, we use comparative transcriptomics to demonstrate the transcriptional similarities and differences during conidial germination and initial colony establishment in a plant pathogenic and an endophytic fungus, Fusarium graminearum and M. anisopliae, respectively. We compared the transcriptomes of F. graminearum and M. anisopliae across four stages of conidial germination: fresh conidia, polar growth, hyphal extension, and either first hyphal branching (on medium) or appressorium formation (on barley). F. graminearum exhibited a higher upregulation of CAZyme, specialized metabolite and effector genes compared to M. anisopliae during interaction with the host, particularly in the appressorium stage, reflecting its pathogenic nature. The appressorium structures formed when M. anisopliae conidia germinated on the host. The transcriptome analysis revealed that the fungus produced reduced transcript levels of CAZyme and specialized metabolite genes reflecting a less aggressive host penetration approach. The candidate genes associated with IAA synthesis were upregulated in M. anisopliae during the appressorium stage, supporting its endophytic lifestyle and suggests that the fungus uses a phytohormone based strategy to interact with plant hosts. Collectively, our findings expand the transcriptome resources and provide valuable insights into the gene networks involved in conidial germination and initiation of infection in pathogenic versus endophytic fungus.
Project description:Conidial germination marks the beginning of the fungal life cycle, and understanding the genes associated with conidial germination provides insights into fungal pathogenicity and host interactions. Here, we use comparative transcriptomics to demonstrate the transcriptional similarities and differences during conidial germination and initial colony establishment in a plant pathogenic and an endophytic fungus, Fusarium graminearum and M. anisopliae, respectively. We compared the transcriptomes of F. graminearum and M. anisopliae across four stages of conidial germination: fresh conidia, polar growth, hyphal extension, and either first hyphal branching (on medium) or appressorium formation (on barley). F. graminearum exhibited a higher upregulation of CAZyme, specialized metabolite and effector genes compared to M. anisopliae during interaction with the host, particularly in the appressorium stage, reflecting its pathogenic nature. The appressorium structures formed when M. anisopliae conidia germinated on the host. The transcriptome analysis revealed that the fungus produced reduced transcript levels of CAZyme and specialized metabolite genes reflecting a less aggressive host penetration approach. The candidate genes associated with IAA synthesis were upregulated in M. anisopliae during the appressorium stage, supporting its endophytic lifestyle and suggests that the fungus uses a phytohormone based strategy to interact with plant hosts. Collectively, our findings expand the transcriptome resources and provide valuable insights into the gene networks involved in conidial germination and initiation of infection in pathogenic versus endophytic fungus.
Project description:Although some mechanisms are known how plant growth beneficial bacteria help plants to grow under stressful conditions, we still know little how the metabolism of host plants and bacteria is coordinated during the establishment of functional interaction. In the present work, using single and dual transcriptomics, we studied the reprograming of metabolic and signaling pathways of Enterobacter sp. SA187 with Arabidopsis thaliana during the change from free-living to endophytic host-microbe interaction. We could identify major changes in primary and secondary metabolic pathways in both the host and bacteria upon interaction, with an important role of the sulfur metabolism and retrograde signaling in mediating plant resistance to salt stress. Also, we studied the effect of SA187 endogenous compounds and its role on sulfur metabolism and consequently salt tolerance. These data should help future research in the field of beneficial plant-microbe interactions for developing sophisticated strategies to improve agriculture of crops under adverse environmental conditions. transcriptome of Arabidopsis thaliana organs with beneficial microbe, beneficial microbe endogenous compound, and ethylene precursor
Project description:High ambient temperature regulated the plant systemic response to the beneficial endophytic fungus Serendipita indica. Most plants in nature establish symbiotic associations with endophytic fungi in soil. Beneficial endophytic fungi induce a systemic response in the aboveground parts of the host plant, thus promoting the growth and fitness of host plants. Meanwhile, temperature elevation from climate change widely affects global plant biodiversity as well as crop quality and yield. Over the past decades, great progresses have been made in the response of plants to high ambient temperature and to symbiosis with endophytic fungi. However, little is known about their synergistic effect on host plants. The endophytic fungus Serendipita indica colonizes the roots of a wide range of plants, including Arabidopsis. Based on the Arabidopsis-S. indica symbiosis experimental system, we analyzed the synergistic effect of high ambient temperature and endophytic fungal symbiosis on host plants. By transcriptome analysis, we found that DNA replication-related genes were significantly upregulated during the systemic response of Arabidopsis aboveground parts to S. indica colonization. Plant hormones, such as jasmonic acid (JA) and ethylene (ET), play important roles in plant growth and systemic responses. We found that high ambient temperature repressed the JA and ET signaling pathways of Arabidopsis aboveground parts during the systemic response to S. indica colonization in roots. Meanwhile, PIF4 is the central hub transcription factor controlling plant thermosensory growth under high ambient temperature in Arabidopsis. PIF4 is also involving JA and/or ET signaling pathway. We found that PIF4 target genes overlapped with many differentially expressed genes (DEGs) during the systemic response, and further showed that the growth promotion efficiency of S. indica on the pif4 mutant was higher than that on the wild type plants.