Dynamic measurement of cytosolic pH and [NO <sub>3</sub> <sup>−</sup> ] uncovers the role of the vacuolar transporter AtCLCa in cytosolic pH homeostasis
Elsa Demes, Laetitia Besse, Paloma Cubero‐Font, Béatrice Satiat‐Jeunemaître, Sébastien Thomine, Alexis De Angeli
Abstract
Significance Intracellular transporters are key actors in cell biological processes. Their disruption causes major physiological defects. Intracellular ion transporters are usually thought to control luminal conditions in organelles; meanwhile, their potential action on cytosolic ion homeostasis is still a black box. The case of a plant Chloride Channel (CLC) is used as a model to uncover the missing link between the regulation of conditions inside the vacuole and inside the cytosol. The development of an original live imaging workflow to simultaneously measure pH and anion dynamics in the cytosol reveals the importance of an Arabidopsis thaliana CLC, AtCLCa, in cytosolic pH homeostasis. Our data highlight an unsuspected function of endomembrane transporters in the regulation of cytosolic pH.