Zonda is a novel early component of the autophagy pathway

ROMERO, N.M; COLOMBO, M.I; MELANI M.; AGUILERA, M.; VALKO, A.; WAPPNER, P; JUHASZ, G

California

Conferencia; 58th Annual Drosophila Research Conference; 2017

Autophagy is an evolutionary conserved process by which eukaryotic cells undergo self-digestion of cytoplasmic components. Here we report that a novel Drosophila immunophilin, which we have named Zonda, is critically required for starvation-induced autophagy. We have found that Zonda is required at early stages of the process, specifically for Vps34-mediated phosphatidylinsositol-3-phosphate deposition. Zonda displays a cytoplascmic distribution under basal conditions, and soon after starvation nucleates in foci associated with the endoplasmic reticulum that colocalize with omegasome markers. Zonda nucleation depends on Atg1, Atg13 and Atg17 but does not require Vps34, Vps15, Atg6 or Atg14. We propose that Zonda is an early component of the autophagy cascade required for Vps34-dependent PI3P deposition and omegasome formation.