Search results for "Sugar transport"
showing 10 items of 14 documents
Arbuscular mycorrhiza - studies on the geosiphon symbiosis lead to the characterization of the first glomeromycotan sugar transporter
2007
Article Addendum ; International audience; The intimate arbuscular mycorrhiza (AM) association between roots and obligate symbiotic Glomeromycota (‘AM fungi’) ‘feeds’ about 80% of land plants. AM forming fungi supply land plants with inorganic nutrients and have an enormous impact on terrestrial ecosystems. In return, AM fungi obtain up to 20% of the plant‑fixed CO2, putatively as monosaccharides. In a recent work we have reported the characterization of the first glomeromycotan monosaccharide transporter, GpMST1, and its gene sequence. We discuss that AM fungi might take up sugars deriving from plant cell‑wall material. The GpMST1 sequence delivers valuable data for the isolation of orthol…
Réponses des cellules de Nicotiana tabacum à des molécules microbiennes : évènements de signalisation précoce, influence de la dynamique membranaire …
2018
In their natural environment plants are in close interaction with beneficial, neutral, or pathogenic microbes, which are highly dependent on carbon resources exuded by plant roots. Sugar transport, which is a key process of plant physiology, is essential to support the fate of plant-microbe interactions. During evolution, plants have acquired the ability to perceive microbial molecules, initiating specific signal transduction cascades and leading to adapted response for microbe lifestyles (avirulent, virulent, or benefic). Plant survival will depend on the nature of the induced mechanisms. My PhD work, carried out on a simplified experimental system, contributes to the understanding of mech…
Membrane dynamics of sugar transports in tobacco-microbe interactions
2017
SPEINRAUBIPM DOCT; Plants can influence microorganism population through exudation of sugars notably as carbon source. Indeed, the type of plant-microorganism interaction (PMI) is linked to the trophic exchanges between plant and microorganism. Microorganisms are thus able to “manipulate” the host to modify sugar fluxes. In mycorrhizal symbiosis, the plant has a supply of nutrients by the fungal partner, which in return receives sugars. In pathogenic relationship, the microorganism will divert sugars provided by the plant without compensation. Despite identification of sugar transporters at biotrophic interfaces, molecular and cellular mechanisms by which microorganisms operate the distribu…
The Medicago truncatula sucrose transporter family: characterization and implication of key members in carbon partitioning towards arbuscular mycorrh…
2012
We identified de novo sucrose transporter (SUT) genes involved in long-distance transport of sucrose from photosynthetic source leaves towards sink organs in the model leguminous species Medicago truncatula. The iden- tification and functional analysis of sugar transporters provide key information on mechanisms that underlie carbon partitioning in plant-microorganism interactions. In that way, full-length sequences of the M. truncatula SUT (MtSUT) family were retrieved and biochemical characterization of MtSUT members was performed by heterologous expression in yeast. The MtSUT family now comprises six genes which distribute among Dicotyledonous clades. MtSUT1-1 and MtSUT4-1 are key members…
Identification of Putative Interactors of Arabidopsis Sugar Transporters
2020
International audience; Hexoses and disaccharides are the key carbon sources for essentially all physiological processes across kingdoms. In plants, sucrose, and in some cases raffinose and stachyose, are transported from the site of synthesis in leaves, the sources, to all other organs that depend on import, the sinks. Sugars also play key roles in interactions with beneficial and pathogenic microbes. Sugar transport is mediated by transport proteins that fall into super-families. Sugar transporter (ST) activity is tuned at different levels, including transcriptional and posttranslational levels. Understanding the ST interactome has a great potential to uncover important players in biologi…
Allelic variants of hexose transporter Hxt3p and hexokinases Hxk1p/Hxk2p in strains ofSaccharomyces cerevisiaeand interspecies hybrids
2015
The transport of sugars across the plasma membrane is a critical step in the utilization of glucose and fructose by Saccharomyces cerevisiae during must fermentations. Variations in the molecular structure of hexose transporters and kinases may affect the ability of wine yeast strains to finish sugar fermentation, even under stressful wine conditions. In this context, we sequenced and compared genes encoding the hexose transporter Hxt3p and the kinases Hxk1p/Hxk2p of Saccharomyces strains and interspecies hybrids with different industrial usages and regional backgrounds. The Hxt3p primary structure varied in a small set of amino acids, which characterized robust yeast strains used for the p…
Identification of sugar transporters in arbuscular mycorrhiza, from basic to applied science
2012
Our study focuses on sugar transporters from both plant and fungal partners at the symbiotic interface to better understand biotrophic exchange systems. Thereby, a collection of putative contigs and ESTs of hexose transporters from Medicago truncatula and Fragaria x ananassa will be processed. The full length sequences will be cloned for functional complementation and uptake experiments in transport deficient yeast mutants. This work also investigates the influence of different mycorrhizal fungi on (1) the expression level of sugar transporters and (2) the economically relevant part of F. x ananassa by analyzing its impact on the plant and the fruit. To this aim, combination of phenological…
Réponses des cellules de Nicotiana tabacum à des molécules microbiennes : évènements de signalisation précoce, influence de la dynamique membranaire …
2018
Responses of Nicotiana tabacum cells to microbial molecule treatments: early signaling events,influence of membrane dynamics, and sugar fluxesIn their natural environment plants are in close interaction with beneficial, neutral, or pathogenicmicrobes, which are highly dependent on carbon resources exuded by plant roots. Sugar transport, which isa key process of plant physiology, is essential to support the fate of plant-microbe interactions. Duringevolution, plants have acquired the ability to perceive microbial molecules, initiating specific signaltransduction cascades and leading to adapted response for microbe lifestyles (avirulent, virulent, or benefic).Plant survival will depend on the…
Arbuscular mycorrhiza (AM): the first glomeromycotan sugar transporter is characterized by using the unique geosiphon symbiosis with cyanobacteria to…
2007
International audience; In the arbuscular mycorrhizas (AM), the symbiotic interface is the site of nutrient exchange where the mycobiont receives up to 20% of the photosynthates of the photobiont as carbohydrates. We have, for the first time, functionally characterised a monosaccharide transporter type, represented by GpMST1, putatively playing a role in this process (Schüßler, A., Martin, H., Cohen, D., Fitz, M., and Wipf, D. 2006. Characterization of a carbohydrate transporter from symbiotic glomeromycotan fungi. Nature 444:933-936.). Together with the arbuscular mycorrhizal (AM) fungi, forming endomycorrhiza with the majority of land plants, Geosiphon pyriformis belongs to the Glomeromyc…
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…