# ATG3 is subjected to redox regulation to quarantee ATG8 lipidation under ROS-generating stresses

## TL;DR

This paper shows how the protein ATG3 is regulated by redox signals to support autophagy under stress conditions involving reactive oxygen species.

## Contribution

The study reveals that ATG3 activity is redox-regulated to ensure ATG8 lipidation during ROS-linked stress.

## Key findings

- ATG3 activity in Chlamydomonas reinhardtii is redox-regulated under ROS stress.
- Redox regulation of ATG3 ensures ATG8 lipidation and autophagy progression.
- The mechanism involves reversible cysteine modifications in ATG3.

## Abstract

The conjugation of ATG8 (autophagy-related 8) proteins to the lipid phosphatidylethanolamine (PE) is the result of the coordinated and highly regulated action of several ATG core proteins, including ATG4 proteases and the E1 (ATG7)- and E2 (ATG3)- activating enzymes. Although it has been stablished that ROS signaling plays an important role in autophagy activation, the molecular mechanisms underlying the redox control of ATG proteins remain largely unclear. We have recently shown that ATG3 activity in Chlamydomonas reinhardtii is subjected to reversible redox regulation to ensure ATG8 lipidation and autophagy progression under ROS-linked stress conditions.

Abbreviations: ATG, Autophagy-related; Cys, Cysteine; DTTred, Reduced Dithiothreitol; MM(PEG24), Methyl Polyethylene Glycol Maleimide; NEM: N-ethylmaleimide; PE, Phosphatidylethanolamine; ROS, Reactive Oxygen Species; TOR, Target Of Rapamycin; Trx, Thioredoxin; WT, Wild Type