title: Feline Coronavirus 3c Protein: A Candidate for a Virulence Marker?
abstract: Feline infectious peritonitis virus (FIPV) is highly virulent and responsible for the highly fatal disease feline infectious peritonitis (FIP), whereas feline enteric coronavirus (FECV) is widespread among the feline population and typically causes asymptomatic infections. Some candidates for genetic markers capable of differentiating these two pathotypes of a unique virus (feline coronavirus) have been proposed by several studies. In the present survey, in order to search for markers that can differentiate FECV and FIPV, several clones of the 3a-c, E, and M genes were sequenced from samples obtained from cats with or without FIP. All genes showed genetic diversity and suggested the presence of FCoV mutant spectrum capable of producing a virulent pathotype in an individual-specific way. In addition, all the feline coronavirus FIPV strains demonstrated a truncated 3c protein, and the 3c gene was the only observed pathotypic marker for FCoVs, showing that 3c gene is a candidate marker for the distinction between the two pathotypes when the mutant spectrum is taken into account.
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil; Coronavirus Research Group, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil.
authors.forename: A S
authors.initials: AS
authors.lastname: Hora
authors.affiliation: Department of Pathology, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil.
authors.forename: P O
authors.initials: PO
authors.lastname: Tonietti
authors.affiliation: Coronavirus Research Group, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil.
authors.forename: S A
authors.initials: SA
authors.lastname: Taniwaki
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil; Coronavirus Research Group, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil.
authors.forename: K M
authors.initials: KM
authors.lastname: Asano
authors.affiliation: Department of Pathology, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil.
authors.forename: P
authors.initials: P
authors.lastname: Maiorka
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil; Coronavirus Research Group, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil.
authors.forename: L J
authors.initials: LJ
authors.lastname: Richtzenhain
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil; Coronavirus Research Group, School of Veterinary Medicine, University of São Paulo, Avenida Professor Dr. Orlando Marques de Paiva 87, Cidade Universitária, 05508-270 São Paulo, SP, Brazil.
authors.forename: P E
authors.initials: PE
authors.lastname: Brandão
mesh_terms: D000818:Animals; D002415:Cats; D016765:Coronavirus, Feline / Q000235:genetics* / Q000472:pathogenicity*; D016766:Feline Infectious Peritonitis / Q000821:virology; D005814:Genes, Viral / Q000235:genetics*; D005819:Genetic Markers / Q000235:genetics*; D014644:Genetic Variation / Q000235:genetics; D009154:Mutation / Q000235:genetics; D010802:Phylogeny; D014764:Viral Proteins / Q000235:genetics*; D014774:Virulence / Q000235:genetics*
chemical_list: D005819:Genetic Markers; D014764:Viral Proteins