Autophagy induced by avian reovirus enhances viral replication in chickens at the early stage of infection

Abstract

Background Avian reovirus (ARV) is an important pathogen that can cause serious disease in poultry. Though several in vitro studies revealed some molecular mechanisms that are responsible for ARV-induced autophagy, it is still largely unknown how ARV manipulates autophagy to promote its own propagation. Results In this study, we demonstrated that ARV infection triggered autophagy in chicken tissues, evident from the enhancement of LC3-I/−II conversion and the appearance of abundant autophagosomes. Moreover, viral replication and the expression of IL-1β were coupled with the process of ARV-induced autophagy in the early stage of infection. Furthermore, regulation of autophagy affected the accumulation of LC3-II, the production of ARV and the expression of IL-1β. Conclusions Altogether, our data suggest that ARV induces autophagy, which benefits its replication and dissemination in chicken tissues at the early infection stage. Electronic supplementary material The online version of this article (10.1186/s12917-019-1926-5) contains supplementary material, which is available to authorized users.

Reovirus Activated Cell Death Pathways

“…Much of our insight into how ReoV activates autophagy comes from work on avian ReoV strains (e.g., GX/2010/1), which promote autophagy by upregulating 1A/1B light chain 3B (LC3) and downregulating the mammalian target of rapamycin (mTOR), a negative regulator of autophagic signaling [ 100 ] ( Figure 3 ). Avian ReoV strains utilize autophagic signaling to increase their own reproduction and dissemination by mechanisms that are as-yet undetermined [ 85 , 101 ]. In agreement with this observation, ablating PI3K or autophagy related lipidation proteins 3 and 5 (ATG3/5) in ReoV infected cancer cells reduces viral replication and the amount of progeny virions produced [ 86 , 102 ].…”

“…For example, inhibition of apoptosis in CNS tissues leads to a significant drop in replication, but a similar trend has not been observed in the intestines, heart, liver, or other tissues from ReoV-infected mice [ 92 , 93 , 95 , 96 ]. Conversely, inhibition of autophagy during infection with avian ReoV was associated with increased progeny in chicken tissues [ 85 , 86 , 101 , 102 ]. Whether autophagy has a similar pro-viral role during mammalian ReoV infections, and the cell types in which this autophagy is important for ReoV replication, remains undefined.…”

Cholesterol-Rich Lipid Rafts in the Cellular Membrane Play an Essential Role in Avian Reovirus Replication

“…Vero cells were maintained in Dulbecco's modified Eagle's medium (DMEM; Gibco, Shanghai, China) supplemented with 10% fetal bovine serum (FBS) (Gibco) at 37 • C with 5% CO 2 . The ARV strain GX/2010/1 was isolated by our laboratory and was propagated in chicken embryo fibroblast (CEF) cells (Meng et al, 2012;Duan et al, 2015;Niu et al, 2017Niu et al, , 2019.…”

“…Filipin III was purchased from Cayman (Michigan, United States). A mouse monoclonal antibody against σC of ARV and polyclonal antibodies against µNS and p10 of ARV were prepared by our laboratory (Duan et al, 2015;Niu et al, 2019…”

Seroprevalence and risk factors of avian reovirus in backyard chickens in different areas of Mymensingh district in Bangladesh

“…Additionally, ARV can be isolated from affected tissues and organs [ 18 ]. Because of having diversified pathogenicity, ARV may cause various diseases, disease conditions, and abnormalities in domestic poultry, including enteric-respiratory diseases, hepatitis, myocarditis, pericarditis, and hydropericardium [ 19 ]. Of these diseases, viral arthritis or tenosynovitis is the disease condition that causes lameness in the chickens.…”