Description du projet
Détailler le mécanisme de l’autophagie chez les plantes
L’autophagie fait référence à l’auto-alimentation ou à l’autodigestion des composants cellulaires. Il s’agit d’un processus extrêmement complexe et dynamique qui contribue à l’homéostasie des cellules et des organismes, à l’adaptation au stress et au maintien de la santé cellulaire. Les composants endommagés ou inutiles sont séquestrés dans des structures spécialisées à double membrane appelées autophagosomes, qui fusionnent ensuite avec les lysosomes. Une compréhension précise de l’autophagie est essentielle pour protéger les organismes contre des maladies telles que la neurodégénérescence, le cancer et les infections. Financé par le Conseil européen de la recherche, le projet AutoRecon se propose d’étudier les mécanismes de formation des autophagosomes dans les cellules eucaryotes à l’aide de techniques biochimiques et de biologie cellulaire. Les chercheurs détermineront les principaux facteurs et leur mode d’action, ce qui permettra de mieux comprendre la formation de novo des organites.
Objectif
I propose to study how eukaryotic cells generate autophagosomes, organelles bounded by a double membrane. These are formed during autophagy and mediate the degradation of cytoplasmic substances within the lysosomal compartment. Autophagy thereby protects the organism from pathological conditions such as neurodegeneration, cancer and infections. Many core factors required for autophagosome formation have been identified but the order in which they act and their mode of action is still unclear. We will use a combination of biochemical and cell biological approaches to elucidate the choreography and mechanism of these core factors. In particular, we will focus on selective autophagy and determine how the autophagic machinery generates an autophagosome that selectively contains the cargo.
To this end we will focus on the cytoplasm-to-vacuole-targeting pathway in S. cerevisiae that mediates the constitutive delivery of the prApe1 enzyme into the vacuole. We will use cargo mimetics or prApe1 complexes in combination with purified autophagy proteins and vesicles to reconstitute the process and so determine which factors are both necessary and sufficient for autophagosome formation, as well as elucidating their mechanism of action.
In parallel we will study selective autophagosome formation in human cells. This will reveal common principles and special adaptations. In particular, we will use cell lysates from genome-edited cells in combination with purified autophagy proteins to reconstitute selective autophagosome formation around ubiquitin-positive cargo material. The insights and hypotheses obtained from these reconstituted systems will be validated using cell biological approaches.
Taken together, our experiments will allow us to delineate the major steps of autophagosome formation during selective autophagy. Our results will yield detailed insights into how cells form and shape organelles in a de novo manner, which is major question in cell- and developmental biology.
Champ scientifique
Mots‑clés
Programme(s)
Régime de financement
ERC-COG - Consolidator GrantInstitution d’accueil
1010 Wien
Autriche