Project description:Purpose: we here adress the gene regulation of G.rosea in response to plant signals in the switch from asymbiotic to presymbiotic growth. Methods: -Strigolactone response: Spores of G.rosea were treated with GR24 (a synthetic strigolactone analog) and collected at 2 days after treatment. Control conditions: spores treated with solvent (M medium acetone 0.1%. Assay and control were performed in triplicates. -Root exsudate response: a cellophane membrane allowing molecule exchanges was deposited on in vitro Daucus carotta roots. Spores were spotted on this membrane and collected 10 days later. Control conditions: spores were spotted on cellophane membrane directly deposited on solid M medium. Assay and control were performed in triplicates. -Fungal gene expression were analyzed on mRNA were sequenced by Illumina HiSeq. sequencing Reads were firstly used in the de novo assembly of Gigaspora rosea Non Redundent Virtual Transcript and then mapped on the assembled transcriptome using CLC genomics workbench. Results: while GR24 triggered the regulation of only few genes which includes 32 genes upregulated (fold chang >2; FDR<0,05, experiment difference>10) and 61 downregulated (fold change < -2; FDR<0,05,experiment difference>10) genes, root exudates regulated several times more genes. A total of 390 genes were up-regulated by root exudates and 442 genes were down-regulated. Moreover, a majority of the genes (23 of 32 upregulated and 25 of 61 downregulated genes) regulated by GR24 were also regulated by root exudates. This is in consistant with the fact that strigolactones secreted from plant root are already characterized as a group of plant signals during AM symbiosis. The result that a large part of genes were differentialy expressed in reponse to root exudates but not GR24 suggested the presence of other plant signals than strigolactones. Conclusions: as a key player during the switch from asymbiotic to presymbiotic growth of G.rosea, plant root secreted signals - including but not limited to striglactones - significantly modified the expression of many G.rosea genes. The genes differentially expressed are mainly involved in oxidation-redution and metabolic processes that might contribute to prepare G.rosea for the following steps of symbiotic association with the host plant.
Project description:Purpose: We here wanted to describe the gene regulation of Gigaspora rosea in association with phyllogenetically divergent plant hosts, and compare these results with gene regulation occuring in R. irregularis, the model arbuscular mycorrhizal fungus. Methods: mRNA from Medicago truncatula (legume), Brachypodium distachyon (grass) in association with G. rosea, and extra radical mycelium of G.rosea were sequenced by Illumina. Reads were mapped on a in-house de novo transcript assembly with the software CLC workbench. Fungal gene expression in the different host plants was compared to extra radical hyphae as reference. Results: Sets of 1891 and 1566 G. rosea genes were highly overexpressed (fold change >5 ; FDR <0,05 and experimental value difference > 10) , in M. truncatula and B. distachyon respectively compared to ERM, among which 802 of them were up-regulated in both plants. Non common up-regulated genes are mainly found non statistically robust in one condition. Conclusions: Our study represents the first transcriptomic analysis on several hosts for this fungal species. These results showed that the interaction between plants and AMF is highly conserved.
Project description:Physcomitrella patens gametophores were treated with exudates from the arbuscular mycorrhiza fungi (AMF) Rhizophagus irregularis (formerly known as Glomus intraradices) and Gigaspora margerita for one hour and 24 hours.
Project description:Most vascular flowering plants have the ability to form mutualistic associations with soil fungi from the Glomeromycota. The resulting symbiosis is called an arbuscular mycorrhiza and they are widespread in terrestrial ecosystems throughout the world. Significant alteration occurs at physiological and molecular levels in both symbionts. To gain a better understanding of the AM symbiosis, we use a 16000 feature oligonucleotide based array to examine gene expression in an arbuscular mycorrhizal symbioses, M. truncatula/Gigaspora gigantea. Keywords: Medicago truncatula, Mycorrhizal, Gigaspora gigantea, microarray profiling
Project description:Elucidating the genetic control of development of C3 and C4 photosynthesis. Atriplex rosea (C4) and Atriplex prostrata (C3) were studied along a leaf developmental gradient to compare development between C3 and C4. C3 Atriplex prostrata x C4 Atriplex rosea F1 hybrid were studied along the same developmental gradient and will aid in identifying regulatory elements involved in C3 and C4 leaf development.
Project description:Pteris cretica L var. nervosa is one of the dominent fern species at antimony mining area where arbuscular mycorrhizal fungi can be found as a symbiosis. The effect of AMF on fern exposed to long-term excessive Sb was pooly understood. The project applied this fern co-cultivting with or withour AMF under different concentration of Sb in soil for charicterising Sb phytomediation ability of it along with the effect by AMF symbiosis.