0000000001205709
AUTHOR
Dominique Morandi
showing 18 related works from this author
TheMedicago truncatulahypermycorrhizal B9 mutant displays an altered response to phosphate and is more susceptible toAphanomyces euteiches
2014
Inorganic phosphate (Pi) plays a key role in the development of arbuscular mycorrhizal (AM) symbiosis, which is favoured when Pi is limiting in the environment. We have characterized the Medicago truncatula hypermycorrhizal B9 mutant for its response to limiting (P/10) and replete (P2) Pi. On P2, mycorrhization was significantly higher in B9 plants than in wild-type (WT). The B9 mutant displayed hallmarks of Pi-limited plants, including higher levels of anthocyanins and lower concentrations of Pi in shoots than WT plants. Transcriptome analyses of roots of WT and B9 plants cultivated on P2 or on P/10 confirmed the Pi-limited profile of the mutant on P2 and highlighted its altered response t…
Influence of arbuscular mycorrhizal colonisation on cadmium induced Medicago truncatula root isoflavonoid accumulation.
2012
Cadmium is a serious environmental pollution threats to the planet. Its accumulation in plants affects many cellular functions, resulting in growth and development inhibition, whose mechanisms are not fully understood. However, some fungi forming arbuscular mycorrhizal symbiosis with the majority of plant species have the capacity to buffer the deleterious effect of this heavy metal. In the present work we investigated the capacity of Rhizophagus irregularis (syn. Glomus irregularis) to alleviate cadmium stress in Medicago truncatula. In spite of a reduction in all mycorrhizal parameters, plants colonized for 21 days by R. irregularis and treated by 2 mg kg(-1) cadmium displayed less growth…
Symbiosis-related plant genes modulate molecular responses in an arbuscular mycorrhizal fungus during early root interactions.
2009
To gain further insight into the role of the plant genome in arbuscular mycorrhiza (AM) establishment, we investigated whether symbiosis-related plant genes affect fungal gene expression in germinating spores and at the appressoria stage of root interactions. Glomus intraradices genes were identified in expressed sequence tag libraries of mycorrhizal Medicago truncatula roots by in silico expression analyses. Transcripts of a subset of genes, with predicted functions in transcription, protein synthesis, primary or secondary metabolism, or of unknown function, were monitored in spores and germinating spores and during interactions with roots of wild-type or mycorrhiza-defective (Myc–) mutan…
Characterization and purification of a bacterial chlorogenic acid esterase detected during the extraction of chlorogenic acid from arbuscular mycorrh…
2016
International audience; A Gram-negative bacterium able to grow using chlorogenic acid (5-caffeoylquinic acid) as sole carbon source has been isolated from the roots of tomato plants inoculated with the arbuscular mycorrhizal fungus Rhizophagus irregularis. An intracellular esterase exhibiting very high affinity (K-m = 2 mu M) for chlorogenic acid has been extracted and purified by FPLC from the chlorogenate-grown cultures of this bacterium. The molecular mass of the purified esterase determined by SDS-PAGE was 61 kDa and its isoelectric point determined by chromatofocusing was 7.75. The esterase hydrolysed chlorogenic acid analogues (caffeoylshikimate, and the 4- and 3-caffeoylquinic acid i…
Transcription of two blue copper-binding protein isogenes is highly correlated with arbuscular mycorrhizal development in Medicago truncatula.
2010
International audience; Expression profiling of two paralogous arbuscular mycorrhizal (AM)-specific blue copper-binding gene (MtBcp1a and MtBcp1b) isoforms was performed by real-time quantitative polymerase chain reaction in wild-type Medicago truncatula Jemalong 5 (J5) during the mycorrhizal development with Glomus intraradices for up to 7 weeks. Time-course analysis in J5 showed that expression of both MtBcp1 genes increased continuously and correlated strongly with the colonization intensity and arbuscule content. MtPT4, selected as a reference gene of the functional plant-fungus association, showed a weaker correlation to mycorrhizal development. In a second experiment, a range of mycor…
Detection of a plant enzyme exhibiting chlorogenate-dependant caffeoyltransferase activity in methanolic extracts of arbuscular mycorrhizal tomato ro…
2012
When Glomus intraradices-colonised tomato roots were extracted in methanol at 6 degrees C, chlorogenic acid (5-caffeoylquinic acid), naturally present in the extract, was slowly converted by transesterification into methyl caffeate. The progress of the reaction could be monitored by HPLC. The reaction only occurred when the ground roots were left in contact with the hydro-alcoholic extract and required the presence of 15-35% water in the mixture. When the roots were extracted in ethanol, chlorogenic acid was transformed to ethyl caffeate in the same conditions. The reaction was also detected in Glomus mosseae-colonised tomato root extracts. It was also detectable in non-mycorrhizal root ext…
Could subcellular proteomics of root plastids teach us more about mycorrhizal symbiosis?
2007
International audience; The arbuscular mycorrhizal (AM) symbiosis is a mutualistic association between soil-borne fungi and the roots of most plant species. Involving the bilateral exchange of nutrients, the symbiosis is connected to drastic changes in plant cell organelle morphology and physiology. Root plastids, in particular, are forming extensive, network-like structures covering the main symbiotic interface, i.e., intracellular, highly branched haustorium-like fungal structures called arbuscules. These plastid networks are highly dynamic and are formed and degraded concomitantly with the formation and degradation of arbuscules. By producing basic metabolic building blocks like fatty ac…
High-troughput TILLING to identify symbiosis-related plant gene function in arbuscular mycorrhiza
2006
International audience
Blue-copper binding proteins of Medicago truncatula: Characterization of the expression of two genes related to the arbuscular mycorrhizal symbiosis
2009
International audience; Expression profiling of two paralogous arbuscular mycorrhizal (AM)-specific blue copper-binding gene (MtBcpla and MtBcp1b) isoforms was performed by real-time quantitative polymerase chain reaction in wild-type Medicago truncatula Jemalong 5 (J5) during the mycorrhizal development with Glomus intraradices for up to 7 weeks. Timecourse analysis in J5 showed that expression of both MtBcp1 genes increased continuously and correlated strongly with the colonization intensity and arbuscule content. MtPT4, selected as a reference gene of the functional plant-fungus association, showed a weaker correlation to mycorrhizal development. In a second experiment, a range of mycorr…
Influence of nitrogen on accumulation of isosojagol ( a newly detected coumestan in soybean ) and associated isoflavonoids in roots and nodules of my…
1991
International audience
Induction of coumestans by the mycorrhizal fungus Glomus intraradices in roots of different Myc- mutants of Medicago truncatula
2001
National audience
Effect of cadmium on growth, isoflavonoid and protein accumulation patterns in mycorrhizal roots of Medicago truncatula
2007
International audience; Ecosystems are submitted to various abiotic stresses, among which heavy metals represent major industrial pollutants. Cadmium (Cd), that has damaging effects on plant metabolism, occurs in agricultural environments through industrial pollution and human activities, including phosphate fertiliser and sewage sludge applications. Metal availability to plants can be modulated by soil microorganisms, including arbuscular mycorrhizal (AM) fungi. In the present work, Cd effects on the model legume Medicago truncatula inoculated or not with the AM fungus Glomus intraradices have been studied at 3 levels: (1) plant biomass production together with green part chlorophyll quant…
The arbuscular mycorrhizal symbiosis a modulator of cadmium stress
2008
International audience; Ecosystems are submitted to various abiotic stresses, among which heavy metals represent major industrial pollutants. Cadmium (Cd), that has damaging effects on plant metabolism, occurs in agricultural environments through industrial pollution and human activities, including phosphate fertiliser and sewage sludge applications. Metal availability to plants can be modulated by soil microorganisms, such as arbuscular mycorrhizal (AM) fungi. In the present work, Cd effects on the model legume Medicago truncatula inoculated or not with the AM fungus Glomus intraradices have been studied at 3 levels: (1) plant biomass production together with green part chlorophyll quantif…
Influence of nitrate on accumulation of isoflavonoids in roots and nodules of mycorrhizal and no mycorrhizal soybean
1990
International audience
The Medicago truncatula hypermycorrhizal B9 mutant displays an altered response to phosphate and is more susceptible to Aphanomyces euteiches.
2014
SPE IPM; National audience; Inorganic phosphate (Pi) plays a key role in the development of arbuscular mycorrhizal (AM) symbiosis, which is favoured when Pi is limiting in the environment. We have characterized the Medicago truncatula hypermycorrhizal B9 mutant for its response to limiting (P/10) and replete (P2) Pi. On P2, mycorrhization was significantly higher in B9 plants than in wild-type (WT). The B9 mutant displayed hallmarks of Pi-limited plants, including higher levels of anthocyanins and lower concentrations of Pi in shoots than WT plants. Transcriptome analyses of roots of WT and B9 plants cultivated on P2 or on P/10 confirmed the Pi-limited profile of the mutant on P2 and highli…
Supernodulation mutants of Pisum sativum and Medicago truncatula : characterization of the mutants and their symbiosis with Rhizobium and arbuscular …
2000
International audience
Comparison between a myc- pea cultivar (Frisson) and one of its myc- mutant (P2) in their ability to produce defense reactions after elicitation with…
1994
International audience
Phosphorus tolerance of an hypermycorrhizal mutant of Medicago truncatula
2010
International audience