Cytosolic malate and oxaloacetate activate S-type anion channels in Arabidopsis guard cells.

ABSTRACT: Intracellular malate-starch interconversion plays an important role in stomatal movements. We investigated whether malate or oxaloacetate from the cytosolic membrane side regulate anion channels in the plasma membrane of Arabidopsis thaliana guard cells. Physiological concentrations of cytosolic malate have been reported in the range of 0.4-3 mM in leaf cells. Guard cell patch clamp and two-electrode oocyte voltage-clamp experiments were pursued. We show that a concentration of 1 mM cytosolic malate greatly activates S-type anion channels in Arabidopsis thaliana guard cells. Interestingly, 1 mM cytosolic oxaloacetate also activates S-type anion channels. Malate activation was abrogated at 10 mM malate and in SLAC1 anion channel mutant alleles. Interestingly, malate activation of S-type ani

SUBMITTER: Wang C 

PROVIDER: S-EPMC6115288 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature