Structural and metabolic dynamics of plant cells in context of heat acclimation

Abstract text (incl. figure legends and references)

In order to survive sub-lethal heat stress, plants possess the ability to acclimate to moderately elevated temperatures. They are altering their physiology in many different ways to maintain cellular homeostasis despite the change in environmental conditions. The carbohydrate metabolism is important for energy storage and biomass production and is also involved in regulation of heat acclimation response. To accurately resolve subcellular metabolic fluxes and compartment-specific metabolite concentrations in the model organism Arabidopsis thaliana, it is necessary to combine metabolic and ultrastructural data. To achieve this, we combined a non-aqueous fractionation procedure to generate subcellular metabolite concentrations with 3D imaging of leaf tissue by serial block-face scanning electron microscopy, which resulted in two datasets of control and heat treated leaf tissue, spanning approximately 150 µm in x and y and 50 µm in z-direction. We were able to calculate effective metabolite concentrations in three compartments of the cell, namely chloroplast, cytosol and vacuole. Applying a kinetic model of carbohydrate metabolism, subcellular fluxes were estimated which revealed metabolic heat acclimation strategies of plant metabolism and provide evidence for a tightly regulated metabolic network.

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Seydel, C., Kitashova, A., Fürtauer, L., & Nägele, T. (2022). Temperature-induced dynamics of plant carbohydrate metabolism. Physiol. Plant, 174(1). e13602. https://doi.org/10.1111/ppl.13602