Measuring Anion and H+ fluxes in guard cells to reveal ion transporters activity

RDP seminar by Alexis De Angeli from BPMP (Montpellier, France)

Abstract : Anion transporters/channels of the plasma and vacuolar membranes are key actors of guard-cells responses to environmental stimuli. Anion transport systems are necessary to mediate stomata movements. During stomata opening/closure guard-cells undergo massive H+-coupled fluxes of (an)ions (like Cl- and NO3-) between the apoplast, the cytosol and the vacuole. These fluxes induce a change of the guard-cell osmotic potential leading to changes of the cellular volume. All the ionic fluxes between the apoplast and the vacuole go through the cytosol. Thus ion transport at the plasma and vacuolar membranes need coordination. This opens the question of the regulation of ionic gradients across the guard-cell plasma and the vacuolar membranes. To address this poorly explored issue, we developed the use of a fluorescent biosensor enabling to simultaneously measure the cytosolic pH and [NO3-, Cl-] in Arabidopsis guard-cells.

Date : Monday, September 30th
Time : 11am
Location : Salle des Thèses

RDP host : Christophe Godin