Thursday 20th October — at 12.00 pm — Salle Jules Bordet (Bât.67)
Invited Speaker : Yair Botbol
From Albert Einstein College of Medicine, Bronx, NY
Hosted by Eric Batsché and Christian Muchardt
Abstract : Macroautophagy is a cellular process that mediates the degradation in the lysosome of cytoplasmic proteins and organelles. Previous studies have shown that macroautophagy is induced in T cells following activation to regulate organelle homeostasis and the cell’s energy metabolism. However, little is still known about the signaling pathways that initiate and regulate activation-induced macroautophagy in T cells. Herein, we show that activation-induced macroautophagy in T cells depends on signaling induced by common gamma-chain cytokines. Consequently, inhibition of signaling through JAK1/3, induced downstream of cytokine receptors containing the common gamma-chain, prevents full induction of macroautophagy in activated T cells. Interestingly, activation-induced autophagy constitutes a non-canonical form of macroautophagy that is independent of mTOR activation but dependent on Beclin1 activity. Our data also show that macroautophagy induction in T cells is associated with an increase of LC3 expression that appears to be mediated by a post-transcriptional mechanism. Overall, our findings unveiled a new role for common gamma-chain cytokines as a molecular link between non-canonical autophagy-induction and T cell activation.