ER stress induces autophagy in yeast cells. Autophagy is a cellular process that degrades and recycles long-lived proteins and damaged organelles. This study demonstrates that ER stress activates autophagy by inducing the formation of the pre-autophagosomal structure (PAS). ER stress leads to the accumulation of misfolded proteins, which activates the unfolded protein response (UPR), promoting the expression of chaperones and proteins involved in recovery. ER stress also stimulates autophagosome formation and transport to the vacuole in an Atg protein-dependent manner. Atg1 kinase activity is influenced by both nutritional status and autophagic state, with starvation-induced autophagy increasing Atg1 activity. The study shows that ER stress induces an autophagic response, as evidenced by the localization of Atg8 at the PAS and the processing of GFP-Atg8 and precursor Ape1. Additionally, ER stress induces the UPR, as indicated by the upregulation of Kar2, an ER chaperone. The results suggest that ER stress can induce autophagy through Atg protein-dependent pathways. The study also shows that ER stress leads to the incorporation of radioactive amino acids, indicating that cells are not in a starvation state. The findings highlight the role of ER stress in inducing autophagy, which is essential for cellular homeostasis and survival under stress conditions.ER stress induces autophagy in yeast cells. Autophagy is a cellular process that degrades and recycles long-lived proteins and damaged organelles. This study demonstrates that ER stress activates autophagy by inducing the formation of the pre-autophagosomal structure (PAS). ER stress leads to the accumulation of misfolded proteins, which activates the unfolded protein response (UPR), promoting the expression of chaperones and proteins involved in recovery. ER stress also stimulates autophagosome formation and transport to the vacuole in an Atg protein-dependent manner. Atg1 kinase activity is influenced by both nutritional status and autophagic state, with starvation-induced autophagy increasing Atg1 activity. The study shows that ER stress induces an autophagic response, as evidenced by the localization of Atg8 at the PAS and the processing of GFP-Atg8 and precursor Ape1. Additionally, ER stress induces the UPR, as indicated by the upregulation of Kar2, an ER chaperone. The results suggest that ER stress can induce autophagy through Atg protein-dependent pathways. The study also shows that ER stress leads to the incorporation of radioactive amino acids, indicating that cells are not in a starvation state. The findings highlight the role of ER stress in inducing autophagy, which is essential for cellular homeostasis and survival under stress conditions.