Incidence of phosphate variations on nutrient transports in a symbiocosm formed by poplar, sorghum and Rhizophagus irregularis.
Ontology highlight
ABSTRACT:
ORGANISM(S): Rhizophagus irregularis Sorghum bicolor Populus trichocarpa
PROVIDER: GSE138316 | GEO | 2019/10/27
REPOSITORIES: GEO
Similar Datasets
Project description:In arbuscular mycorrhizal (AM) symbiosis, key components of nutrient uptake and exchange are specialized transporters that facilitate nutrient transport across membranes. As phosphate is a nutrient and a regulator of nutrient exchanges, we investigated the effect of P availability to extraradical mycelium (ERM) on both plant and fungus transcriptomes and metabolomes in a symbiocosm system. By perturbing nutrient exchanges under the control of P, our objectives were to identify new fungal genes involved in nutrient transports, and to characterize in which extent the fungus differentially modulates its metabolism when interacting with two different plant species. We performed transportome analysis on the ERM and intraradical mycelium of the AM fungus Rhizophagus irregularis associated to Populus trichocarpa and Sorghum bicolor under high and low P availability in ERM, using quantitative RT-PCR and Illumina mRNA-sequencing. We observed that mycorrhizal symbiosis induces expression of specific phosphate and ammonium transporters in both plants. Furthermore, we identified new AM-inducible transporters and showed that a subset of phosphate transporters is regulated independently of symbiotic nutrient exchange. mRNA-Sequencing revealed that the fungal transportome was not similarly regulated in the two host plant species according to P availability. Mirroring this effect, many plant carbohydrate transporters were down-regulated in P. trichocarpa mycorrhizal root tissue. Metabolome analysis revealed further that AM root colonization led to a modification of root primary metabolism under low and high P availability and to a decrease of primary metabolite pools in general. Moreover, the down regulation of the sucrose transporters suggests that the plant limits carbohydrate long distance transport (i.e. from shoot to the mycorrhizal roots). By simultaneous uptake/reuptake of nutrients from the apoplast at the biotrophic interface, plant and fungus are both able to control reciprocal nutrient fluxes.
| S-EPMC6920215 | biostudies-literature
Project description:Incidence of phosphate variations on nutrient transports in a symbiocosm formed by poplar, sorghum and Rhizophagus irregularis.
| PRJNA575690 | ENA
Project description:Purpose: The recent publication of the fungal mutualist R. irregularis genome facilitated transcriptomic studies. We here adress the gene regulation of R. irregularis in response to root exudates from rice wild-type and osnope1 (no perception candidate - mutant unable to host arbuscular mycorrhizal fungi) Methods: Spores of R. irregularis were treated with root exudates and collected at 1 hour, 24 hours and 7 days after addition. To monitor fungal gene regulation, control conditions were also prepared at T0, 1h, 24h and 7d. mRNA were sequenced by HiSeq Illumina. Reads were mapped on the Rhizophagus irregularis genome assembly (Gloin1 - Tisserant et al., PNAS, 2013) using CLCworkbench suite. Results: -At 1h, a set of 92 fungal genes were found up-regulated in response to wt root exudates (92), not to osnope1 root exudates, many of them being involved in cell signaling. -At 24h and 7d, numerous genes putatively involved in primary metabolism were up-regulated in response to wt root exudates, not in response to osnope1 root exudates -Several vital genes involved in cell development are repressed in response to osnope1 RE compared to wt RE. Conclusions: these results argue for a high metabolic activity induced by wt root exudates, not by osnope1 root exudates.
2017-02-04 | GSE65595 | GEO
Project description:Purpose: The recent publication of the fungal mutualist R. irregularis genome facilitated transcriptomic studies. We here adress the gene regulation of R. irregularis in response to plant signals in the switch from asymbiotic to presymbiotic growth Methods: Spores of R. irregularis were treated with GR24 (strigolactone synthetic analog) and collected at 1 hour, 2 days, 7 days and 14 days after induction. To stimulate the fungus with root exudates, a cellophane membrane allowing molecule exchanges was deposited on in vitro Daucus carotta roots. Spores were spotted on this membrane and collected 14 days after. To monitor fungal gene regulation, control conditions were also prepared and mRNA were sequenced by HiSeq Illumina. Read were mapped on the genome assembly with CLCworkbench Results: At 1 hour, GR24 triggered the overexpression (fold change >2; FDR<0,05) of 123 genes and the repression (fold change < -2; FDR<0,05) of 17 genes. At 2 days, 33 genes were induced, 13 repressed ; at 7 days 106 genes were induced and 13 repressed and at 14 days 19 genes were induced and 10 repressed. Few genes overlap between the different time point. Root exudates induced 251 genes and repressed 63 genes. Few genes were regulated by both GR24 and root exudates. Conclusions: GR24 kinetic showed that fungal gene regulation is sequential, quick and involves hundreds of genes. Among those genes, a chitin synthase, involved either in fungal growth either in symbiotic signal production was strongly induced at 1hour, 7 days and 14 days. As few genes are regulated in response to root exudates and GR24, we propose that other plant signals play a role in ealy steps and trigger fungal gene regulation. Several genes coding for putative secreted peptides were induced in response to these plant signals. These genes might be effectors involved in early plant defense manipulation, then facilitating root entry. Thus, they are good candidates to investigate early steps of plant penetration.
2018-02-01 | GSE67913 | GEO
Project description:Arbuscular mycorrhizal fungi arguably form the most successful and wide-spread endosymbiosis with plants. In general terms there is very little host-specificity in this interaction, indicating an extremely broad compatibility. However, host preferences as well as varying symbiotic efficiencies have been observed, the molecular basis of which is still largely unknown. Secreted proteins (SPs) may act as fungal effectors to control symbiotic efficiency in a host-dependent manner. Therefore, we studied whether AM fungi adjust their secretome in a host- and stage-dependent manner to contribute to their extremely wide host-range. We investigated the expression of SP encoding genes of R. irregularis DAOM197198 in three evolutionary distantly related plant species, Medicago truncatula (Medicago), Nicotiana benthamiana (Nicotiana) and Allium schoenoprasum (Chives). In addition we used laser microdissection in combination with RNAseq to study SP expression at different stages of the symbiotic interaction in Medicago. Our data indicate that the vast majority of 288 expressed SPs show equal expression levels in the interaction with all three host plants. In addition, a subset (~15%) of the SPs show significant differential expression depending on the host plant and/or environmental condition. This host-dependent expression appears to be controlled locally in the hyphal network in response to host metabolic cues. Overall, this study offers a comprehensive analysis of the R. irregularis secretome, which now offers a solid basis to direct functional studies on the role of fungal SPs in AM symbiosis.
2018-03-27 | GSE99655 | GEO
Project description:One of the bottlenecks in mycorrhiza research is that arbuscular mycorrhizal fungi (AMF) have to be cultivated with host plant roots. Some AMF species, such as Rhizophagus irregularis, can be grown in vitro on dual-compartment plates, where fungal material can be harvested from a fungus-only compartment. Plant roots often grow into this fungus compartment, and regular root trimming is required if the fungal material needs to be free of traces of plant material. Trimming also increases unwanted contamination by other microorganisms. We compared 22 different culture types and conditions to a widely used dual-compartment culture system that we refer to as the "standard system." We found two modified culture systems that allowed high spore production and low rates of contamination. We then compared the two modified culture systems with the standard system in more detail. In the two modified culture systems versus the standard system, a comparable number of spores were produced per plate, the necessity for root trimming was reduced, and there was significantly diminished contamination in the fungal compartment. A cost analysis showed that both modified culture systems were more economic than the standard culture system for the production of the same number of non-contaminated spores. The two modified culture systems provide an economic alternative for the production of contaminant-free fungal material which is ideal for studies requiring AMF DNA or RNA for genetics, genomics, and transcriptomic studies or for studies requiring relatively large amounts of fungal material for greenhouse experiments.
| S-EPMC5486606 | biostudies-literature
Project description:Arbuscular mycorrhizal symbiosis is a mutualistic interaction between most land plants and fungi of the glomeromycotina subphylum. The initiation, development and regulation of this symbiosis involve numerous signalling events between and within the symbiotic partners. Among other signals, phytohormones are known to play important roles at various stages of the interaction. During presymbiotic steps, plant roots exude strigolactones which stimulate fungal spore germination and hyphal branching, and promote the initiation of symbiosis. At later stages, different plant hormone classes can act as positive or negative regulators of the interaction. Although the fungus is known to reciprocally emit regulatory signals, its potential contribution to the phytohormonal pool has received little attention, and has so far only been addressed by indirect assays. In this study, using mass spectrometry, we analyzed phytohormones released into the medium by germinated spores of the arbuscular mycorrhizal fungus Rhizophagus irregularis. We detected the presence of a cytokinin (isopentenyl adenosine) and an auxin (indole-acetic acid). In addition, we identified a gibberellin (gibberellin A4) in spore extracts. We also used gas chromatography to show that R. irregularis produces ethylene from methionine and the α-keto γ-methylthio butyric acid pathway. These results highlight the possibility for AM fungi to use phytohormones to interact with their host plants, or to regulate their own development.
| S-EPMC7567356 | biostudies-literature
Project description:Rhizophagus irregularis Transcriptome sequencing
| PRJNA486540 | ENA
Project description:Rhizophagus irregularis Raw sequence reads
| PRJNA286097 | ENA
Project description:Rhizophagus irregularis gene regulation in response to rice root exudates
| PRJNA274445 | ENA