Les séminaires ont lieu sur le Campus Montpellier Institut Agro/INRA de La Gaillarde (2, place P. Viala Montpellier)

Vendredi 1er juillet 2022 à 14h – Amphi 2 (Bât 2bis)


Mike Blatt

University of Glasgow, UK


What can we learn from mechanistic models of guard cell membrane transport

Stomata of most plants close to preserve water when the demand for CO2 by photosynthesis is reduced. Stomatal responses are slow compared to photosynthesis, and this kinetic difference erodes assimilation and water use efficiencies under fluctuating light. Despite a deep knowledge of guard cells that regulate the stoma, efforts to enhance stomatal kinetics are limited by our understanding of its control by foliar CO2. Here I discuss how mechanistic modelling of stomatal guard cells can be used to understand how membrane transport integrates across the plasma membrane and endomembrane compartments. I focus on our recent advances in modelling that incorporates CO2 diffusion and mesophyll carbon fixation within the OnGuard modelling platform. These studies uncover a central role for endomembrane Ca2+ stores in guard cell responsiveness to fluctuating light and CO2. Modelling predicted, and experiments demonstrate a latency, or ‘carbon memory’, in guard cells that affects stomatal dynamics, photosynthesis and water use by the plant. These findings illustrate the power of modelling to bridge the gap from the molecule to the plant, and they offer a powerful tool with which to explore membrane transport in the context of cellular and whole-plant physiology.

contact : anne-alienor.very@cnrs.fr