title: Dengue-induced autophagy, virus replication and protection from cell death require ER stress (PERK) pathway activation.
abstract: A virus that reproduces in a host without killing cells can easily establish a successful infection. Previously, we showed that dengue-2, a virus that threatens 40% of the world, induces autophagy, enabling dengue to reproduce in cells without triggering cell death. Autophagy further protects the virus-laden cells from further insults. In this study, we evaluate how it does so; we show that dengue upregulates host pathways that increase autophagy, namely endoplasmic reticulum (ER) stress and ataxia telangiectasia mutated (ATM) signaling followed by production of reactive oxygen species (ROS). Inhibition of ER stress or ATM signaling abrogates the dengue-conferred protection against other cell stressors. Direct inhibition of ER stress response in infected cells decreases autophagosome turnover, reduces ROS production and limits reproduction of dengue virus. Blocking ATM activation, which is an early response to infection, decreases transcription of ER stress response proteins, but ATM has limited impact on production of ROS and virus titers. Production of ROS determines only late-onset autophagy in infected cells and is not necessary for dengue-induced protection from stressors. Collectively, these results demonstrate that among the multiple autophagy-inducing pathways during infection, ER stress signaling is more important to viral replication and protection of cells than either ATM or ROS-mediated signaling. To limit virus production and survival of dengue-infected cells, one must address the earliest phase of autophagy, induced by ER stress.
authors.affiliation: Department of Biology, Queens College and Graduate Center of the City University of New York, Flushing, NY, USA.
authors.forename: E
authors.initials: E
authors.lastname: Datan
authors.affiliation: Department of Biology, Queens College and Graduate Center of the City University of New York, Flushing, NY, USA.
authors.forename: S G
authors.initials: SG
authors.lastname: Roy
authors.affiliation: Department of Biology, Queens College and Graduate Center of the City University of New York, Flushing, NY, USA.
authors.forename: G
authors.initials: G
authors.lastname: Germain
authors.affiliation: Department of Biology, Queens College and Graduate Center of the City University of New York, Flushing, NY, USA.
authors.forename: N
authors.initials: N
authors.lastname: Zali
authors.affiliation: Department of Biology, Queens College and Graduate Center of the City University of New York, Flushing, NY, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: McLean
authors.affiliation: Department of Biology, Queens College and Graduate Center of the City University of New York, Flushing, NY, USA.
authors.forename: G
authors.initials: G
authors.lastname: Golshan
authors.affiliation: Department of Biology, Queens College and Graduate Center of the City University of New York, Flushing, NY, USA.
authors.forename: S
authors.initials: S
authors.lastname: Harbajan
authors.affiliation: Department of Biology, Queens College and Graduate Center of the City University of New York, Flushing, NY, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Lockshin
authors.affiliation: Department of Biology, Queens College and Graduate Center of the City University of New York, Flushing, NY, USA.
authors.forename: Z
authors.identifier: http://orcid.org/0000-0003-4386-8072
authors.initials: Z
authors.lastname: Zakeri
mesh_terms: D000818:Animals; D001343:Autophagy; D006224:Cricetinae; D003715:Dengue / Q000378:metabolism*; D003716:Dengue Virus / Q000502:physiology*; D004285:Dogs; D059865:Endoplasmic Reticulum Stress; D020935:MAP Kinase Signaling System; D061985:Madin Darby Canine Kidney Cells; D014779:Virus Replication / Q000502:physiology*