MOLECULAR CHARACTERIZATION OF AUTOPHAGY‐RELATED GENE 5 FROM Spodoptera exigua AND EXPRESSION ANALYSIS UNDER VARIOUS STRESS CONDITIONS

Abstract

Autophagy is not only involved in development, but also has been proved to attend immune response against invading pathogens. Autophagy protein 5 (ATG5) is an important autophagic protein, which plays a crucial role in autophagosome elongation. Although ATG5 has been well studied in mammal, yeast, and Drosophila, little is known about ATG5 in lepidopteran insects. We cloned putative SeAtg5 gene from Spodoptera exigua larvae by the rapid amplification of cDNA ends method, and its characteristics and the influences of multiple exogenous factors on its expression levels were then investigated. The results showed that the putative S. exigua SeATG5 protein is highly homologous to other insect ATG5 proteins, which has a conserved Pfm domain and multiple phosphorylation sites. Next, fluorescence microscope observation showed that mCherry-SeATG5 was distributed in both nucleus and cytoplasm of Spodoptera litura Sl-HP cells and partially co-localized with BmATG6-GFP, but it almost has no significant co-localization with GFP-HaATG8. Then, the Western blot analysis demonstrated that GFP-SeATG5 conjugated with ATG12. Moreover, real-time PCR revealed that its expression levels significantly increased at the initiation of pupation and the stage of adult. In addition, the expression levels of SeAtg5 can be enhanced by the starvation, UV radiation, and infection of baculovirus and bacterium. However, the expression levels of SeAtg5 decreased at 24 h post treatments in all these treatments except in starvation. These results suggested that SeATG5 might be involved in response of S. exigua under various stress conditions.

Bombyx mori Nuclear Polyhedrosis Virus (BmNPV) Induces Host Cell Autophagy to Benefit Infection

“…Meanwhile, autophagy by TEM at 6 hpi supports the above hypothesis. Proteomic analysis showed the up-regulation of the BmATG3 protein in response to BmNPV infection, and S. exigua SeATG5 can also be enhanced by the infection of baculovirus at 24 h [ 41 , 42 ]. All of these reports coincide with our results, which further confirm that the virus infection causes autophagy and the up-regulation of Atg genes.…”

Spodoptera litura autophagy‐related protein 1 interacts with autophagy‐related protein 5 and enhances its degradation

“…S4). As we had previously constructed the plasmid for SeATG5 expression (Liu et al ., ), SeAtg5 was used in this study instead of SlAtg5 . We first analysed the distribution and colocalization of SlATG1A and SeATG5.…”

Starvation‐induced autophagy in Spodoptera frugiperda Sf9 ovarian cells

“…The Insecta comprises the largest class of arthropods and contains most of the species in the animal kingdom. Drosophila melanogaster is widely used as a model organism for investigating autophagy (Chang & Neufeld, 2010;Delanoue et al, 2010;Guo et al, 2012;Wang et al, 2012;Wei et al, 2012;Gai et al, 2013;Tian et al, 2013;Tracy & Baehrecke, 2013;Liu et al, 2016). Similarly, autophagy is an important biological process in the metamorphosis of Spodoptera frugiperda, a Lepidoptera pest that harms cereal crops.…”