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.
Project description:A transcriptomic approach was implemented using two Penicillium species to identify genes related to fungal aggressiveness in apple fruit and loci contained in ungerminated conidia. Total RNA was isolated from ungerminated conidia and decayed apple fruit infected with P. expansum R19 (aggressive) or P. polonicum RS1 (weak). There were 2,442 differentially expressed genes (DEGs) between the R19 and RS1 in apple and comparisons within species between apple and conidia revealed 4,404 DEGs for R19, and 2935 for RS1, respectively. Gene ontology (GO) revealed differential regulation in fungal transport and metabolism genes expressed during decay, suggesting a flux in nutrient acquisition and detoxification strategies. In R19, the oxidoreductase GO category comprised 20% of all groups differentially expressed in decayed apple verses ungerminated conidia in addition to those involved in hydrogen peroxide metabolism. Ungerminated conidia from both species showed higher expression of genes encoding the glyoxylate shunt and beta-oxidation, specifying the earliest metabolic requirements for germination
Project description:The recent release of a large number of genomes from ectomycorrhizal, orchid mycorrhizal and root endophytic fungi have provided deep insight into fungal lifestyle-associated genomic adaptation. Comparative analyses of symbiotic fungal taxa showed that similar outcomes of interactions in distant related root symbioses are examples of convergent evolution. The order Sebacinales represents a sister group to the Agaricomycetes (Basidiomycota) that is comprised of ectomycorrhizal, ericoid-, orchid- mycorrhizal, root endophytic fungi and saprotrophs (Oberwinkler et al., 2013). Sebacinoid taxa are widely distributed from arctic to temperate to tropical ecosystems and are among the most common and species-rich groups of ECM, OM and endophytic fungi (Tedersoo et al., 2012, Tedersoo et al., 2010, Oberwinkler et al., 2013). The root endophyte Piriformospora indica and the orchid mycorrhizal fungus S. vermifera (MAFF 305830) are non-obligate root symbionts which were shown to be able to interact with many different experimental hosts, including the non-mycorrhizal plant Arabidopsis thaliana. These two fungi display similar colonization strategies in barley and in Arabidopsis and the ability to establish beneficial interactions with different hosts (Deshmukh et al., 2006). Colonization of the roots by P. indica and S. vermifera results in enhanced seed germination and biomass production as well as increased resistance against biotic and abiotic stresses in its experimental hosts, including various members of the Brassicaceae family, barley, Nicotiana attenuata and switchgrass (Ghimire, 2011, Ghimire et al., 2009, Ghimire et al., 2011, Waller et al., 2008, Barazani et al., 2007, Deshmukh et al., 2006). Microarray experiments were performed to identify and characterize conserved sebacinoid genes as key determinants in the Sebacinales symbioses.
2015-06-01 | GSE60736 | GEO
Project description:Endophytic Fungal Community in Huperzia serrata
Project description:Roots of Arabidopsis thaliana do not engage in symbiotic association with mycorrhizal fungi but host taxonomically diverse fungal communities that influence health and disease states. We sequenced the genomes of 41 isolates representative of the A. thaliana root mycobiota for comparative analysis with 79 other plant-associated fungi. We report that root mycobiota members evolved from ancestors having diverse lifestyles and retained diverse repertoires of plant cell wall-degrading enzymes (PCWDEs) and effector-like small secreted proteins. We identified a set of 84 gene families predicting best endophytism, including families encoding PCWDEs acting on xylan (GH10) and cellulose (AA9). These genes also belong to a core transcriptional response induced by phylogenetically-distant mycobiota members in A. thaliana roots. Recolonization experiments with individual fungi indicated that strains with detrimental effects in mono-association with the host not only colonize roots more aggressively than those with beneficial activities but also dominate in natural root samples. We identified and validated the pectin degrading enzyme family PL1_7 as a key component linking aggressiveness of endophytic colonization to plant health.
2021-11-03 | GSE169629 | GEO
Project description:Fungal community in wheat roots
Project description:Piriformospora indica, an endophytic fungus of Sebacinales, colonizes the roots of many plant species including Arabidopsis thaliana. The symbiotic interaction promotes plant per-formance, growth and resistance/tolerance against abiotic and biotic stress. We demonstrate that exudated compounds from the fungus activate stress and defense responses in the Arabidopsis roots and shoots before the two partners are in physical contact. They induce stomata closure, stimulate reactive oxygen species (ROS) production, stress-related phytohormone accumulation and activate defense and stress genes in the roots and/or shoots. Once a physical contact is established, the stomata re-open, ROS and phytohormone levels decline, and the gene expression pattern indicates a shift from defense to mutualistic interaction. We propose that exudated compounds from P. indica induce stress and defense responses in the host. Root colonization results in the downregulation of defense responses and the activation of genes involved in promoting plant growth, metabolism and performance. Twelve day-old (48 h cold treatment and 10 days of illumination) Arabidopsis seedlings of equal sizes were selected for co-cultivation experiments. They were transferred to PNM plates with a nylone membrane on the top (Johnson et al. 2011) and exposed to a fungal plug 5 mm in diameter or a KM plug of the same size without fungal hyphae (control). The plugs were placed 3 cm away from the closest root part . The light intensity (80 ± 5 μmol m-2 sec-1) was checked every third day to ensure that both P. indica- and mock-treated seedlings receive equal amounts of light.