Providence virus (family: Carmotetraviridae) replicates vRNA in association with the Golgi apparatus and secretory vesicles

Abstract

Providence virus (PrV) is the sole member of the family Carmotetraviridae (formerly Tetraviridae) sharing the characteristic T54 capsid architecture with other tetravirus families. Despite significant structural similarities, PrV differs from other tetraviruses in terms of genome organization, non-structural protein sequence and regulation of gene expression. In addition, it is the only tetravirus that infects tissue culture cells. Previous studies showed that in persistently infected Helicoverpa zea MG8 cells, the PrV replicase associates with detergent-resistant membranes in punctate cytosolic structures, which is similar to the distribution of an alpha-like tetravirus replicase (Helicoverpa armigera stunt virus). Here, we demonstrate that the site of PrV vRNA replication coincides with the presence of PrV p40/p104 proteins in infected cells and that these replication proteins associate with the Golgi apparatus and secretory vesicles in transfected cells.

Computational characterization of providence virus non-structural proteins: Evolutionary and functional implications

“…Within the PrV p40 surface-exposed region lies a sequence with the potential of adopting an alpha helical supercoil conformation that is characteristic of protein-protein interaction functions (Lupas and Gruber, 2005;Wang et al, 2012). The similarity in location, surface-exposed characteristics with tombusvirus, TBSV p33 interaction domain and structural conformations with protein interaction properties, all together may indicate a probable protein-protein interaction sequence in PrV p40, essential for PrV RNA replication (Walter, 2008;Short et al, 2013).…”

“…The orientation of both proteins across the bilayer is identical with an amino acid stretch located at the extracellular side and two amino acid segments at the intracellular side of the bilayer. The first 52 amino acids of p104 were hypothetically located at the cytosolic side of the membrane, identical to the orientation of TBSV p92 transmembrane topology (Scholthof et al, 1995), and may contain subcellular membrane targeting signals that direct the viral replication complex (VRC) to membranes derived from the Golgi apparatus and/or secretory pathway (Short et al, 2013).…”

“…So far, aspects of tetravirus replication have been limited to studies by subcellular localization with viral RNA and replication proteins. These studies have shown that the replicase of Helicoverpa armigera stunt virus, Alphatetraviridae, associates with membranes derived from endosomes while PrV replicase associates with membrane vesicles from the Golgi apparatus and secretory pathway (Walter, 2008;Short et al, 2010Short et al, , 2013.…”

Golgi Structure and Function in Health, Stress, and Diseases

“…As a highly dynamic organelle, Golgi serves as a membrane scaffold for multiple viruses, including infectious hepatitis C virus, enteroviruses, poliovirus, foot-and-mouth-disease virus, dengue virus, coronavirus, Kunjin virus, tick-borne encephalitis virus, rubella virus, and bunyamwera virus (Miller and Krijnse-Locker 2008;Harak and Lohmann 2015;Risco et al 2003;Salanueva et al 2003;Delgui et al 2013;Westerbeck and Machamer 2015), and is frequently fragmented after infection (Campadelli et al 1993;Salanueva et al 2003;Yadav et al 2016;Avitabile et al 1995;Lavi et al 1996;Hansen et al 2017;Rebmann et al 2016). Viruses use Golgi membranes directly and/or hijack master controllers of Golgi biogenesis and trafficking to generate vesicles that are used as the site of viral RNA replication (Quiner and Jackson 2010;Hansen et al 2017;Short et al 2013), wrapping (Sivan et al 2016;Alzhanova and Hruby 2007;Alzhanova and Hruby 2006;Nanbo et al 2018;Lundu et al 2018;Procter et al 2018), intracellular transduction (Nonnenmacher et al 2015), and secretion ). Viral infection triggers Golgi fragmentation via diverse mechanisms, ranging from phosphorylating key Golgi structural proteins such as GRASP65 (Rebmann et al 2016), activating the Src kinase to phosphorylate the Dynamin 2 GTPase (Martin et al 2017), targeting the immunity-related GTPase M (IRGM) to the Golgi to induce GBF1 phosphorylation (Hansen et al 2017), modulating vesicular trafficking (Yadav et al 2016;Johns et al 2014), to impeding the major histocompatibility complex (MHC) class I trafficking, antigen presentation, and/or cytokine secretion Rohde et al 2012).…”

Providence virus: An animal virus that replicates in plants or a plant virus that infects and replicates in animal cells?

“…zea MG8 cells. Cells were probed with mouse monoclonal anti-dsRNA and anti-mouse AF546 [8]. Viral replicase was stained with biotin-conjugated p40 and streptavidin AF488, while rabbit polyclonal anti-CP and anti-rabbit AF633 were used to detect PrV CP.…”