The GCN2 kinase activates early events of autophagy

Autor: Maurin, Anne-Catherine, B'Chir, Wafa, Parry, Laurent, Carraro, Valerie, Mesclon, Florent, Mordier, Sylvie, Jousse, Céline, Bruhat, Alain, Codogno, Patrice, Averous, Julien, Fafournoux, Pierre
Přispěvatelé: Unité de Nutrition Humaine (UNH), Institut National de la Recherche Agronomique (INRA)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020]), Institut Necker Enfants-Malades (INEM - UM 111 (UMR 8253 / U1151)), Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Université Paris Descartes - Paris 5 (UPD5), Institut National de Recherche Agronomique (INRA). UMR Unité de Nutrition Humaine (1019)., Centre de Recherche en Nutrition Humaine (CRNH). FRA., ProdInra, Archive Ouverte, Unité de Nutrition Humaine - Clermont Auvergne (UNH), Institut National de la Recherche Agronomique (INRA)-Université Clermont Auvergne (UCA)
Jazyk: angličtina
Rok vydání: 2018
Předmět:
Zdroj: 8. Proteasome & Autophagy
8. Proteasome & Autophagy, Institut National de Recherche Agronomique (INRA). UMR Unité de Nutrition Humaine (1019).; Centre de Recherche en Nutrition Humaine (CRNH). FRA., Apr 2018, Clermont-Ferrand, France. 90 p
8. Proteasome & Autophagy, Apr 2018, Clermont-Ferrand, France. 90 p., 2018
Popis: Autophagy Session : Selected oral communication, Poster N°37 Organizing Committee: Chairs: Didier Attaix, Lydie Combaret and Daniel TaillandierAutophagy Session : Selected oral communication, Poster N°37Organizing Committee: Chairs: Didier Attaix, Lydie Combaret and Daniel Taillandier; The protein kinase GCN2 detects free tRNA during stresses of essential amino acid (EAA) deficiencies and triggers an adaptive cell response by phosphorylating eIF2α. This leads to both a decrease in protein synthesis and the emergence of an ATF4-dependent gene expression program. Our previous work provided evidence that the GCN2/p-eIF2α/ATF4 pathway plays a major role in macro-autophagy by upregulating the expression of a number of autophagy-related genes at the transcriptional level, thereby contributing to expand the process over the long term. Here, we aimed at determining whether GCN2 could be involved in the early steps of activation of the autophagic process. Our data showed that autophagy was activated within the first hour of a single EAA deficiency in both cultured cells and mouse liver, a response that required GCN2. Furthermore, we observed that the phosphorylation of eIF2α contributed to this adaptive upregulation of autophagy whereas ATF4 was dispensable. Importantly, by using experimental conditions to activate GCN2 without affecting mTORC1 activity, our data showed that the GCN2-dependent activation of autophagy occurs without requiring concomitant mTORC1 inhibition. Overall these results highlighted that the GCN2/p-eIF2α signaling was sufficient to activate early stages of autophagy upregulation.
Databáze: OpenAIRE