Search results for "Medicago truncatula"
showing 10 items of 90 documents
Effects of indole-3-acetic acid on Sinorhizobium meliloti survival and on symbiotic nitrogen fixation and stem dry weight production
2009
We evaluated the effects of the main auxin phytohormone, indole-3-acetic acid (IAA), on the central metabolism of Sinorhizobium meliloti strain 1021. We either treated the Sinorhizobium meliloti 1021 strain with 0.5 mM IAA (1021+) or use a derivative, RD64, of the same strain harbouring a pathway for IAA biosynthesis converting tryptophan into IAA via indoleacetamide. We assayed the activity of key enzymes in the major energy-yielding pathways (Entner-Doudoroff, Embden-Meyerhof-Parnas, pentose phosphate, glyoxylate bypass and tricarboxylic acid cycle). We found that activity of two main regulative tricarboxylic acid (TCA) cycle enzymes was increased. Citrate synthase (CS) activity, as compa…
Proteome analysis and identification of symbiosis-related proteins from Medicago truncatula Gaertn. by two-dimensional electrophoresis and mass spect…
2002
Time-course analysis of root protein profiles was studied by two-dimensional gel electrophoresis and silver staining in the model plant Medicago truncatula, inoculated either with the arbuscular mycorrhizal fungus Glomus mosseae or with the nitrogen fixing bacterium Sinorhizobium meliloti. Protein modifications in relation to the development of both symbioses included down- and upregulations, as well as newly induced polypeptides. Matrix assisted laser desorption/ionization-time of flight-mass spectrometry after trypsin digestion clearly identified one polypeptide induced in nodulated roots as a M. truncatula leghemoglobin. Internal sequencing with a quadrupole time-of-flight mass spectrome…
Sub-cellular proteomic analysis of a Medicago truncatula root microsomal fraction
2004
Since the last decade, Medicago truncatula has emerged as one of the model plants particularly investigated in the field of plant-microbe interactions. Several genetic and molecular approaches including proteomics have been developed to increase knowledge about this plant species. To complement the proteomic data, which have mainly focused on the total root proteins from M. truncatula, we carried out a sub-cellular approach to gain access to the total membrane-associated proteins. Following the setting up of the purification process, microsomal proteins were separated on 2-DE. Ninety-six out of the 440 well-resolved proteins were identified by MALDI-TOF peptide mass fingerprinting. A high p…
Mutations in DMI3 and SUNN modify the appressorium-responsive root proteome in arbuscular mycorrhiza.
2006
Modification of the Medicago truncatula root proteome during the early stage of arbuscular mycorrhizal symbiosis was investigated by comparing, using two-dimensional electrophoresis, the protein patterns obtained from non-inoculated roots and roots synchronized for Glomus intraradices appressorium formation. This approach was conducted in wild-type (J5), mycorrhiza-defective (TRV25, dmi3), and autoregulation-defective (TR122, sunn) M. truncatula genotypes. The groups of proteins that responded to appressorium formation were further compared between wild-type and mutant genotypes; few overlaps and major differences were recorded, demonstrating that mutations in DMI3 and SUNN modified the ap…
Technical improvements for analysis of recalcitrant proteins by LC-MS : the myccorhiza responsive membrane proteome as a case study
2012
Arbuscular mycorrhizas (AM) are widespread symbiotic associations between plant roots and AM fungi. Deep membrane alterations are the foremost morphological changes occurring in the host plant in response to AM symbiosis. Two-dimensional gel electrophoresis (2-DE) is the workhorse method in AM proteomics. Membrane proteins are under-represented in 2-DE because of their hydrophobicity, low abundance, and precipitation at their isoelectric point, thereby few are the identified membrane proteins involved in sustaining the AM symbiosis. Membrane proteomics is still challenging due to 2-DE related shortcomings, however latest trends and advancements in mass spectrometry (MS)-based quantitative p…
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…
Influence of type III bacterial secretion system on the interactions between plant and non pathogenic fluorescent Pseudomonads spp.
2010
No abstract
Endosperm cintribution to Medicago truncatula seed development : characterization of a DOF transcription factor expressed in chalazal endosperm
2014
In the current context, which necessitates a reduction in inputs in crop systems and boosting of production of plant proteins to reduce France’s dependency on feed imports,, growing legumes represents an alternative. Grain legumes are major sources of proteins for animal and human nutrition. In the UMR1347 Agroécologie, the objectives of the study group "déterminismes Génétiques et Environnementaux de l’Adaptation des Plantes à des Systèmes de culture Innovants" (GEAPSI) are to promote legume cultivation and adaptation to environmental stresses, via multidisciplinary approaches (genetics, ecophysiology, molecular physiology). This thesis project was carried out in the "Étude des Mécanismes …
Medicago truncatula
2012
In plants, long distance transport of sugars from photosynthetic source leaves to sink organs comprises different crucial steps depending on the species and organ types. Sucrose, the main carbohydrate for long distance transport is synthesized in the mesophyll and then loaded into the phloem. After long distance transport through the phloem vessels, sucrose is finally unloaded towards sink organs. Alternatively, sugar can also be transferred to non‐plant sinks and plant colonization by heterotrophic organisms increases the sink strength and creates an additional sugar demand for the host plant. These sugar fluxes are coordinated by transport systems. Main sugar transporters in plants compri…
The underlying processes governing seed size plasticity: Impact of endoploidy on seed coat development and cell expansion in Medicago truncatula
2019
Prod 2019-55a BAP GEAPSI CT1 BAP; Abstract Bigger seeds represent an agronomic and economic benefit but the breeding and ecological balance between seed size and number is difficult to find. Large seeds associated with other practices can improve crop competitiveness as they are more vigorous and result in healthier crops with higher yields, even under stressful conditions. Applying genomic research and genome-wide association studies to breeding is generating new strategies to improve seed traits and novel insights into the biology of seed development and metabolism that are discussed in this chapter. The DNA amount differs among the seed tissues and amplifying genomic DNA by endocycle ind…