Date: 15th September 2021
Title: Environmental and hormonal control of plant hydraulics: molecular and genetic dissection
Location: Remotely via Zoom
Host: Maija Sierla
Abstract: Plant water transport is a key component of plant performance and adaptation to adverse environments. Plasma membrane aquaporins mediate multiple controls of plant tissue hydraulics. New insights into the mechanisms at work in their regulation in roots, leaf veins and stomata will be presented, with emphasis on the major role of phosphorylation. In this context, the PIP2;1 aquaporin, which transports both water and hydrogen peroxide, was shown to play a dual hydraulic and signaling role during stomatal movement. To obtain a better view of root water uptake and its regulation, we also investigated the genetic bases of root hydraulics in Arabidopsis and maize, using quantitative genetics approaches, including linkage mapping and genome-wide association mapping. Several Arabidopsis genes controlling root hydraulics were identified and will be discussed. Finally, we developed a combination of experimental and mathematical modelling approaches which allow a concomitant determination of root radial and axial conductivities and a comprehensive view of root hydraulic architecture.
Christophe Maurel has a long-standing interest in plant water transport. His group uses molecular and physiological approaches to investigate the modes of water transport regulation at the level of cloned aquaporins, purified membranes, living cells or organs like excised roots. In addition, quantitative genetics, root phenotyping and mathematical modeling are combined to address the dynamics of growth and hydraulics in roots, showing how these adapt to environmental constraints.