Open AccessPorcine circovirus 3 capsid protein induces autophagy in HEK293T cells by inhibiting phosphorylation of the mammalian target of rapamycin
Author(s) -
Shichao Geng,
Xiaoliang Li,
Weihuan Fang
Publication year - 2020
Publication title -
journal of zhejiang university. science b
Language(s) - English
Resource type - Journals
eISSN - 1862-1783
pISSN - 1673-1581
DOI - 10.1631/jzus.b1900657
Subject(s) - porcine circovirus , hek 293 cells , autophagy , capsid , microbiology and biotechnology , phosphorylation , pi3k/akt/mtor pathway , transfection , biology , ubiquitin , cell culture , virology , chemistry , signal transduction , virus , gene , apoptosis , genetics
Porcine circovirus 3 (PCV3) has been detected in major pig-producing countries around the world since its first report in the US in 2016. Most current studies have focused on epidemiological investigations and detection methods of PCV3 because of lack of live virus strains for research on its pathogenesis in porcine cells or even in pigs. We constructed a recombinant plasmid pCMV-Cap carrying the PCV3 orf2 gene to investigate the effects of capsid (Cap) protein expression on autophagic response in human embryonic kidney cell line 293T (HEK293T). We demonstrate that PCV3 Cap protein induced complete autophagy shown as formation of autophagosomes and autophagosome-like vesicles as well as LC3-II conversion from LC3-I via inhibiting phosphorylation of the mammalian target of rapamycin (mTOR) in HEK293T cells. The ubiquitin-proteasome pathway is also involved in the autophagy process. These findings provide insight for further exploration of PCV3 pathogenetic mechanisms in porcine cells.