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bioRxiv · 10.1101/2025.04.29.651223

Acclimation of carbon metabolism to a changing environment across a leaf rosette of Arabidopsis thaliana

Abstract

O_LIPlants need to efficiently and quickly stabilize photosynthesis and carbon metabolism under changing environmental conditions to prevent irreversible tissue damage C_LIO_LIDifferently developed leaves of Arabidopsis thaliana rosettes are typically homogenized for metabolic analyses which might result in significant over- or underestimation of metabolite dynamics. C_LIO_LIHere, photosynthesis and carbon metabolism were analysed in mature and immature leaves of rosettes of natural Arabidopsis accessions originating from southern and northern Europe. Ambient growth condition at 22 {degrees}C was compared to a combined low temperature/elevated light treatment. C_LIO_LIGradients of Fv/Fm and CO2 assimilation rates across leaf rosettes hinted towards tissue-specific acclimation capacities of photosynthesis and carbon metabolism. C_LIO_LIDynamics of carbohydrates and carboxylic acids were integrated with photosynthetic parameters in a quantitative carbon balance model. Model simulations suggested that mature leaf tissue stabilizes acclimation of carbon metabolism in immature leaf tissue and/or other sink tissue. C_LIO_LIIn conclusion, acclimation capacities of photosynthesis to low temperature and elevated light significantly differ within one leaf rosette of Arabidopsis. This directly affects carbon metabolism which shapes the metabolic acclimation capacity of the whole plant. C_LIO_LIIt is suggested to consider such tissue-specific effects which might otherwise be hidden behind a high variance of experimental data. C_LI

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Brodsky, V., Kerscher, A., Urban, M., Naegele, T.. 2025-05-03. Acclimation of carbon metabolism to a changing environment across a leaf rosette of Arabidopsis thaliana. https://doi.org/10.1101/2025.04.29.651223

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