Description du projet
Sortir des ténèbres: comprendre les flux métaboliques chez les eucaryotes phototrophes
La plupart d’entre nous sont familiers avec les rythmes circadiens, une synchronisation interne oscillante qui se conforme à la rotation de la Terre en 24 heures. Les processus métaboliques y sont fortement liés de manière à optimiser l’utilisation de l’énergie tout au long du cycle lumière-obscurité. De même, les transitions entre l’obscurité et la lumière sont très importantes pour les phototrophes, qui tirent leur énergie de la lumière du soleil grâce à la photosynthèse. Les transitions obscurité-lumière provoquent des changements dans l’état redox des composants photosynthétiques qui modulent les flux métaboliques. Le projet CHLARABIDOX, financé par l’UE, étudie la dynamique, à l’échelle du protéome, de réponse à la lumière chez deux espèces phototrophes (l’algue verte Chlamydomonas reinhardtii et la plante Arabidopsis thaliana). La haute résolution temporelle des changements métaboliques liés à l’oxydoréduction induite par la lumière pourrait aider à manipuler les processus énergétiques de production de biocombustibles et à identifier les modifications qui permettent aux plantes de s’adapter au changement climatique.
Objectif
Most organisms exhibit a diurnal metabolic cycle, especially phototrophs, whose metabolism is strictly dependent on light. Dark-light transitions are accompanied by dramatic changes in the redox state of photosynthetic components, which drives redox-based post-translational modification of protein cysteines, whose oxidation state can considerably impact protein activity, and thus regulate metabolism. Given the central role of redox metabolism in biology, the operation of thiol-disulphide based switches are well-appreciated as a metabolic acclimation strategy, and the study of cysteine modifications in proteomes is a major interest of contemporary biology. The objective of CHLARABIDOX is to go beyond inventories of redox modified proteins by monitoring the proteome-wide dynamics of disulphide-dithiol status in the context of a diurnal metabolic cycle in phototrophic eukaryotes, specifically, the green alga Chlamydomonas reinhardtii and the land plant Arabidopsis thaliana. An innovative chemoproteomic isoTOP-ABPP approach will be used in an experimental design with deep temporal resolution to capture a good fraction of the proteome with site specificity and quantitative information about reactivity. The discoveries will be made in the context of a body of literature on thioredoxin-dependent redox regulation of central carbon metabolism, which will serve as a priori validation. The outcome of the project is a proteome-wide view of the operation of regulatory redox sensors, anchored to accompanying rich datasets on physiology, metabolic potential, transcriptomics, proteomics and central metabolites, which would inform the operation of light-driven metabolic networks. Both systems are compatible with downstream modelling of diurnal metabolic fluxes and validation by reverse genetics approaches. A long term impact on strategies for manipulating metabolism for biofuels production, or manipulating photosynthesis for better acclimation to climate change is also envisioned.
Champ scientifique
- natural sciencesbiological sciencesbiochemistrybiomoleculesproteinsproteomics
- natural sciencesbiological sciencesmicrobiologyphycology
- natural scienceschemical scienceselectrochemistryelectrolysis
- natural sciencesearth and related environmental sciencesatmospheric sciencesclimatologyclimatic changes
- natural sciencesbiological sciencesbotany
Mots‑clés
Programme(s)
Régime de financement
MSCA-IF - Marie Skłodowska-Curie Individual Fellowships (IF)Coordinateur
41004 Sevilla
Espagne