Project description:The crop species Solanum lycopersicum establishes a beneficial root- symbiosis with the widespread group of arbuscular mycorrhizal (AM) fungi. The mycorrhiza establishment leads to a modulation of the plant gene expression which is not restricted to the root compartment but spreads at the organism-wide level. To understand the systemic effect of the fungal presence on the tomato fruit, we performed global transcriptome profiling through RNA-Seq analysis on Moneymaker tomato fruits sampled at the turning ripening stage. Gene expression data were obtained from fruits sampled at 55 days after flowering. Fruits were collected from Funneliformis mosseae colonized plants and from control plants which were fertilized in order to avoid responses related to nutrient deficiency.
Project description:The mutualistic arbuscular mycorrhizal (AM) symbiosis arose in land plants more than 450 million years ago. This symbiosis is still widely found across major land plant lineages, including bryophytes. Despite its broad taxonomic distribution, little is known about the molecular components underpinning symbiosis outside of flowering plants. Here, we demonstrate that a broad AM genetic programme is conserved amongst land plants. In this study, we characterised the dynamic response of the liverwort Marchantia paleacea to Rhizophagus irregularis colonization by time-resolved transcriptomics across three stages of symbiosis. Comparative analysis of transcriptional responses to symbiosis in the liverwort M. paleacea and the legume Medicago truncatula further revealed evolutionarily conserved expression patterns for genes underpinning pre-symbiotic signalling, intracellular colonization and nutrient exchange. This study demonstrates that the genetic machinery regulating key aspects of symbiosis in plant hosts is largely conserved and coregulated across land plants.
Project description:To investigate the involvement of arbuscular mycorrhizal symbiosis in the moleular regulation in foxtail millet roots and the effects of genetic variation on AMS-mediated molecular regulation, we isolated total RNA from the roots of 3 different landraces for comprehensive transcriptomic analysis. We then performed gene expression profiling analysis using data obtained from RNA-seq of 3 different landraces (Hanevalval, TT8, ICE36) after 6-week mock or arbuscular mycorrhizal fungi treatments.
Project description:The involvement of nuclear factor Y (NF-Y) in transcriptional reprogramming during arbuscular mycorrhizal symbiosis has been demonstrated in several plant species. However, a comprehensive picture is lacking. We showed that the spatial expression of NF-YC3 was observed in cortical cells containing arbuscules via the cis-regulatory element GCC boxes. Moreover, NF-YC3 promoter was transactivated by the combination of CYCLOPS and autoactive CCaMK via GCC boxes. Knockdown of NF-YC3 significantly reduced the abundance of all intraradical fungal structures and affected arbuscules size. BCP1, SbtM1, and WRI5a, whose expression was correlated with NF-YC3 level, might be downstream of NF-YC3. NF-YC3 interacted with one of three NF-YBs, NF-YB3a, NF-YB5c, or NF-YB3b, in yeast and in planta, and interacted with NF-YA3a in yeast. Spatial expression of three NF-YBs was observed in all cell layers of roots under both mock and mycorrhizal conditions. Knockdown of three NF-YBs collectively, but not individually, reduced the fungal colonization level, suggesting that there might be functional redundancy of NF-YBs to regulate AM symbiosis. Collectively, our data suggest that NF-YC3 and NF-YBs positively regulate AM symbiosis in tomato, and arbuscule-related NF-YC3 may be important downstream gene of common symbiosis signaling pathway.
Project description:affy_ams_maize - aafy_ams_maize - Main objectives of this study: - role of plant cell wall during AM symbiosis - regulation pattern during AM symbiosis - understanding of the original mycorrhizal phenotype of bm4 - search of candidate-genes to study AM symbiosis-After 7 days in phytochambers, plantlets were transplanted in 2L of humidified bedrock with 3000 spores for inoculation conditions or without spore for mock conditions then plants have grown in greenhouse. Maize roots have been sampled 7 weeks post-inoculation and freezed in liquid nitrogen then stocked at -80°C. Total RNA was isolated from frozen root tissue by using the RNeasy Plant Mini Kit (Qiagen) following the manufacturer’s instructions. Keywords: treated vs untreated comparison
Project description:The symbiotic interaction of plants with arbuscular mycorrhizal fungi (AM fungi) is ancient and widespread. Plants provide AM fungi with carbon in exchange for nutrients and water, making this interaction a prime target for crop improvement. However, plant-fungal interactions are restricted to a small subset of root cells, precluding the application of most conventional functional genomic techniques to study the molecular bases of these interactions. Here we used single-nucleus and spatial RNA sequencing to explore both M. truncatula and R. irregularis transcriptomes in AM symbiosis at cellular and spatial resolution. Integrated spatially-registered single-cell maps of interacting cells revealed major infected and uninfected plant root cell types. We observed that cortical cells exhibit distinct transcriptome profiles during different stages of colonization by AM fungi, indicating dynamic interplay between both organisms during establishment of the cellular interface enabling successful symbiosis. Our study provides insight into a symbiotic relationship of major agricultural and environmental importance and demonstrates a paradigm combining single-cell and spatial transcriptomics for the analysis of complex organismal interactions.
Project description:The symbiotic interaction of plants with arbuscular mycorrhizal fungi (AM fungi) is ancient and widespread. Plants provide AM fungi with carbon in exchange for nutrients and water, making this interaction a prime target for crop improvement. However, plant-fungal interactions are restricted to a small subset of root cells, precluding the application of most conventional functional genomic techniques to study the molecular bases of these interactions. Here we used single-nucleus and spatial RNA sequencing to explore both M. truncatula and R. irregularis transcriptomes in AM symbiosis at cellular and spatial resolution. Integrated spatially-registered single-cell maps of interacting cells revealed major infected and uninfected plant root cell types. We observed that cortical cells exhibit distinct transcriptome profiles during different stages of colonization by AM fungi, indicating dynamic interplay between both organisms during establishment of the cellular interface enabling successful symbiosis. Our study provides insight into a symbiotic relationship of major agricultural and environmental importance and demonstrates a paradigm combining single-cell and spatial transcriptomics for the analysis of complex organismal interactions.
Project description:Arbuscular mycorrhizal (AM) symbiosis that associates roots of most land plants with soilborne fungi (Glomeromycota), is characterized by reciprocal nutritional benefits. Fungal colonization of plant roots induces massive changes in cortical cells where the fungus differentiates an arbuscule, which drives proliferation of the plasma membrane, and the de novo synthesis of the periarbuscular membrane. Despite the recognized importance of membrane proteins in sustaining AM symbiosis, the root microsomal proteome elicited upon mycorrhiza still remains to be explored. In this study, we first examined the qualitative composition of the root membrane proteome of Medicago truncatula after microsome enrichment and subsequent in depth analysis by GeLC-MS/MS. The results obtained highlighted the identification of 1226 root membrane protein candidates whose cellular and functional classifications predispose plastids and protein synthesis as prevalent organelle and function, respectively. Changes at the protein abundance level between the membrane proteomes of mycorrhizal and nonmycorrhizal roots were further monitored by spectral counting, which retrieved a total of 97 proteins that displayed a differential accumulation upon AM symbiosis. Besides the canonical markers of the periarbuscular membrane, new candidates supporting the importance of membrane trafficking events during mycorrhiza establishment/functioning were identified, including flotillin-like proteins.
Project description:affy_ams_maize - aafy_ams_maize - Main objectives of this study: - role of plant cell wall during AM symbiosis - regulation pattern during AM symbiosis - understanding of the original mycorrhizal phenotype of bm4 - search of candidate-genes to study AM symbiosis-After 7 days in phytochambers, plantlets were transplanted in 2L of humidified bedrock with 3000 spores for inoculation conditions or without spore for mock conditions then plants have grown in greenhouse. Maize roots have been sampled 7 weeks post-inoculation and freezed in liquid nitrogen then stocked at -80M-BM-0C. Total RNA was isolated from frozen root tissue by using the RNeasy Plant Mini Kit (Qiagen) following the manufacturerM-bM-^@M-^Ys instructions. Keywords: treated vs untreated comparison 8 arrays - maize
Project description:To date, little is known about molecular mechanisms by which woody plants engage symbiosis with arbuscular mycorrhizal (AM) fungi. Here we investigated transcriptome changes in the roots of Poncirus trifoliata (the most common citrus rootstock) that are induced during colonization of an AM fungus Glomus versiforme (Gv). A total of 282 Poncirus genes were differentially expressed in response to Gv colonization, of which 138 could identify homologous genes from the model legume Medicago truncatula that also exhibit similar AM-induced transcriptional changes, while the remaining 144 do not. A high proportion of the AM-responsive Poncirus genes are predicted to be involved in transcription regulation, transport process, cellular organization and protein degradation, implicating these processes in the establishment of AM symbiosis. Promoter-GUS analysis of six AM-induced Poncirus genes [encoding an exocyst subunit (PtrEXO70I), two transcription factors (PtNAC1 and PtPALM1), one chitinase (PtrChit2), one plastid movement associated protein (PtrPMI2) and one lipase (PtrLipase3)] showed that all of them exhibit specific expression in arbuscule-containing root cortical cells, suggesting their potential involvement in establishing AM symbiosis. Notably, down-regulation of the ortholog of PtrExo70I in Medicago by RNAi significantly impaired arbuscule development, indicating that Exo70I is an important host component required for arbuscule development in root cortical cells. This study not only helps identify conserved host genes engaged in AM symbiosis but should also guide future mechanistic studies of potentially Poncirus-specific events during its symbiosis with AM fungi.