0000000000597585
AUTHOR
Anne-aliénor Véry
Recherche de systèmes de transport de potassium impliqués dans le transfert de K+ de la mycorhize arbusculaire au riz lors d'interactions symbiotiques
Les champignons mycorhiziens à arbuscules (CMA) développent des connexions interdépendantes avec les racines d'environ 90% des espèces végétales. Ces interactions augmentent la disponibilité ainsi que la translocation des nutriments (en particulier N et P), et améliorent ainsi la nutrition et la croissance des plantes. De plus, la résistance à une variété de stress, parmi lesquels le stress salin, s'est avérée améliorée par les interactions CMA-plante, par exemple chez le riz. Des recherches intenses pour expliquer les mécanismes moléculaires des interactions bénéfiques CMA-plante ont conduit à l'identification de transporteurs de phosphate et d'ammonium impliqués dans les échanges de nutri…
Search for potassium transport systems involved in arbuscular mycorrhiza-rice symbiotic interactions
Arbuscular mycorrhizal fungi (AMF) develop interdependent connections with roots of about90% of plant species. These interactions increase availability as well as translocation ofnutrients (especially N and P), and thereby improve plant nutrition and growth. Moreover,resistance to a variety of stresses, among which salt stress, has been shown to be improved byAMF-plant interactions, for example in rice. Intense research to explain the molecularmechanisms of AMF-plant beneficial interactions led to the identification of phosphate andammonium transporters involved in nutrient exchanges from AMF to the plant, in several plantspecies. In spite of the importance of potassium (K+) for plant physi…
Magnesium ions promote assembly of channel-like structures from beticolin 0, a non-peptide fungal toxin purified from Cercospora beticola.
Beticolins are toxins produced by the fungus Cercospora beticola. Using beticolin 0 (B0), we have produced a strong and Mg(2+)-dependent increase in the membrane conductance of Arabidopsis protoplasts and Xenopus oocytes. In protein-free artificial bilayers, discrete deflexions of current were observed (12 pS unitary conductance in symmetrical 100 mM KCl) in the presence of B0 (approximately 10 microM) and in the presence of nominal Mg2+. Addition of 50 microM Mg2+ induced a macroscopic current which could be reversed to single channel current by chelating Mg2+ with EDTA. Both unitary and macroscopic currents were ohmic. The increase in conductance of biological membranes triggered by B0 is…