Starvation-induced autophagy in Spodoptera frugiperda Sf9 ovarian cells: Response of Sf9 cells to autophagy

Autophagy controls insect development and can be targeted for pest control in agriculture. In the present study, starvation-induced autophagy is investigated in the insect species Spodoptera frugiperda. Bioinformatics analysis and a search of the EST database (http://bioweb.ensam.inra.fr/spodobase) identifies a putative ATG8 gene of S. frugiperda. To generate a biomarker of autophagosome, the DNA sequence encoding the open reading frame of this gene is amplified and cloned into a pIEX-4-mCherry-EGFP-SfATG8 recombinant vector. Sf9 cells are then transfected with this expression vector and starved in phosphate-buffered saline solution for 4 h to induce autophagy, which is examined by LysoTracker staining (Life Technologies, Grand Island, New York), western blotting and fluorescence microscopy. The results obtained show that starvation stimulates lipidation of SfATG8-PE and the formation of autophagosomes, providing a foundation for further research with respect to autophagy in insects.