Responses of two insect cell lines to starvation: Autophagy prevents them from undergoing apoptosis and necrosis, respectively

► Autophagy increases in Lepidoptera insect cell lines, SL-ZSU-1 and Bm36 cells under acid starvation. ► At the early stage of starvation, autophagy prevents SL-ZSU-1 and Bm36 cells from undergoing apoptosis and necrosis, respectively. ► After prolonged starvation, SL-ZSU-1 cells died via apoptosis, but Bm36 cells died via autophagic cell death. ► The abundance of saposin-like, Atg6 and caspase-9-like is different between SL-ZSU-1 and Bm36 cells.