title: Characterisation of different forms of the accessory gp3 canine coronavirus type I protein identified in cats.
abstract: ORF3 is a supplemental open reading frame coding for an accessory glycoprotein gp3 of unknown function, only present in genotype I canine strain (CCoV-I) and some atypical feline FCoV strains. In these latter hosts, the ORF3 gene systematically displays one or two identical deletions leading to the synthesis of truncated proteins gp3-Δ1 and gp3-Δ2. As deletions in CoV accessory proteins have already been involved in tissue or host switch, studies of these different gp3 proteins were conducted in canine and feline cell. All proteins oligomerise through covalent bonds, are N-glycosylated and are maintained in the ER in non-infected but also in CCoV-II infected cells, without any specific retention signal. However, deletions influence their level of expression. In canine cells, all proteins are expressed with similar level whereas in feline cells, the expression of gp3-Δ1 is higher than the two other forms of gp3. None of the gp3 proteins modulate the viral replication cycle of heterologous genotype II CCoV in canine cell line, leading to the conclusion that the gp3 proteins are probably advantageous only for CCoV-I and atypical FCoV strains.
authors: Université Paris-Est, Ecole Nationale Vétérinaire d'Alfort, UMR 1161 Virology, Maisons-Alfort, France; INRA, UMR 1161 Virology, Maisons-Alfort, France; ANSES, Animal Health Laboratory, UMR 1161 Virology, Maisons-Alfort, France.
authors: Anne-Laure Pham-Hung d'Alexandry
authors: AL
authors: d'Orengiani
authors: Université Paris-Est, Ecole Nationale Vétérinaire d'Alfort, UMR 1161 Virology, Maisons-Alfort, France; INRA, UMR 1161 Virology, Maisons-Alfort, France; ANSES, Animal Health Laboratory, UMR 1161 Virology, Maisons-Alfort, France.
authors: Lidia
authors: L
authors: Duarte
authors: Université Paris-Est, Ecole Nationale Vétérinaire d'Alfort, UMR 1161 Virology, Maisons-Alfort, France; INRA, UMR 1161 Virology, Maisons-Alfort, France; ANSES, Animal Health Laboratory, UMR 1161 Virology, Maisons-Alfort, France.
authors: Nicole
authors: N
authors: Pavio
authors: Université Paris-Est, Ecole Nationale Vétérinaire d'Alfort, UMR 1161 Virology, Maisons-Alfort, France; INRA, UMR 1161 Virology, Maisons-Alfort, France; ANSES, Animal Health Laboratory, UMR 1161 Virology, Maisons-Alfort, France. Electronic address: slepoder@vet-alfort.fr.
authors: Sophie
authors: S
authors: Le Poder
mesh_terms: D000818:Animals; D002371:Cat Diseases / Q000821:virology*; D002415:Cats; D018352:Coronavirus Infections / Q000662:veterinary* / Q000821:virology; D017939:Coronavirus, Canine / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D020869:Gene Expression Profiling; D006031:Glycosylation; D055503:Protein Multimerization; D011499:Protein Processing, Post-Translational; D017384:Sequence Deletion; D054334:Viral Regulatory and Accessory Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D054334:Viral Regulatory and Accessory Proteins
keywords: Accessory protein; Canine; Coronavirus; Feline; Gp3; Species barrier