The protein kinase ULK1 regulates autophagy induction but its mode of action is poorly understood. Guan and colleagues show that following nutrient starvation, ULK1-mediated phosphorylation of Beclin-1 is required for the activation of VPS34 lipid kinase within the autophagy complex ATG1–VPS34–Beclin-1. They also find that during starvation, the inhibitory effect of mTOR on ULK1 is relieved to increase the phosphorylation of Beclin-1.
- Ryan C. Russell
- Ye Tian
- Kun-Liang Guan