Characterization of a novel bat-HKU2-like swine enteric alphacoronavirus (SeACoV) infection in cultured cells and development of a SeACoV infectious clone

Virology. 2019 Oct;536:110-118. doi: 10.1016/j.virol.2019.08.006. Epub 2019 Aug 9.

Abstract

Swine enteric alphacoronavirus (SeACoV), also known as swine acute diarrhea syndrome coronavirus (SADS-CoV), belongs to the species Rhinolophus bat coronavirus HKU2. Herein, we report on the primary characterization of SeACoV in vitro. Four antibodies against the SeACoV spike, membrane, nucleocapsid and nonstructural protein 3 capable of reacting with viral antigens in SeACoV-infected Vero cells were generated. We established a DNA-launched SeACoV infectious clone based on the cell adapted passage-10 virus and rescued the recombinant virus with a unique genetic marker in cultured cells. Six subgenomic mRNAs containing the leader-body junction sites, including a bicistronic mRNA encoding the accessory NS7a and NS7b genes, were experimentally identified in SeACoV-infected cells. Cellular ultrastructural changes induced by SeACoV infection were visualized by electron microscopy. The availability of the SeACoV infectious clone and a panel of antibodies against different viral proteins will facilitate further studies on understanding the molecular mechanisms of SeACoV replication and pathogenesis.

Keywords: Electron microscopy (EM); Infectious clone; Subgenomic mRNAs; Swine enteric alphacoronavirus (SeACoV); Viral antibodies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alphacoronavirus / genetics*
  • Alphacoronavirus / metabolism
  • Alphacoronavirus / pathogenicity
  • Animals
  • Antibodies, Viral / biosynthesis
  • Antibodies, Viral / chemistry*
  • Antigens, Viral / chemistry*
  • Antigens, Viral / immunology
  • Base Sequence
  • Cell Membrane / ultrastructure
  • Cell Membrane / virology
  • Chiroptera
  • Chlorocebus aethiops
  • Clone Cells
  • Coronavirus Infections / diagnosis
  • Coronavirus Infections / veterinary*
  • Coronavirus Infections / virology
  • DNA, Complementary / genetics
  • DNA, Complementary / metabolism
  • Microscopy, Electron
  • Nucleocapsid / chemistry
  • Nucleocapsid / immunology
  • RNA, Messenger / genetics*
  • RNA, Messenger / metabolism
  • RNA, Viral / genetics*
  • RNA, Viral / metabolism
  • RNA-Dependent RNA Polymerase / chemistry
  • RNA-Dependent RNA Polymerase / immunology
  • Rabbits
  • Spike Glycoprotein, Coronavirus / chemistry
  • Spike Glycoprotein, Coronavirus / immunology
  • Swine
  • Swine Diseases / diagnosis
  • Swine Diseases / virology
  • Vero Cells
  • Viral Nonstructural Proteins / chemistry
  • Viral Nonstructural Proteins / immunology
  • Virus Replication

Substances

  • Antibodies, Viral
  • Antigens, Viral
  • DNA, Complementary
  • RNA, Messenger
  • RNA, Viral
  • Spike Glycoprotein, Coronavirus
  • Viral Nonstructural Proteins
  • RNA-Dependent RNA Polymerase

Supplementary concepts

  • Swine acute diarrhea syndrome coronavirus