Knockout of Atg5 inhibits proliferation and promotes apoptosis of DF-1 cells

Atg5, as a switch of cell autophagy and apoptosis, plays an important regulatory role in the occurrence and development of autophagy. Atg5 has been reported to involve the autophagy process but little in the apoptotic process. Here, we constructed an Atg5(-/-) DF-1 cell line using the CRISPR/Cas9 assay and confirmed the significant difference in growth kinetics between Atg5(-/-) DF-1 cells and wild-type DF-1 cells. Importantly, we found that Atg5 suppresses the cellular proliferation and induce the apoptosis in DF-1 cells by Hoechst's staining, flow cytometry, and caspase activity assay. All these findings indicated that Atg5 plays an important role in the proliferation of DF-1 cells. On the other hand, we compared the expression of autophagy key proteins LC3 and P62 in Atg5 knockout cells and wild-type cells, and detected the aggregation point distribution of LC3 protein in cells by laser confocal technique; our results showed that Atg5 knockout inhibited autophagy compared with wild-type cells. The present findings further help to resolve the molecular mechanisms regulating Atg5 autophagy and apoptosis.