title: Duck TRIM27-L enhances MAVS signaling and is absent in chickens and turkeys.
abstract: Wild waterfowl, including mallard ducks, are the natural reservoir of avian influenza A virus and they are resistant to strains that would cause fatal infection in chickens. Here we investigate potential involvement of TRIM proteins in the differential response of ducks and chickens to influenza. We examine a cluster of TRIM genes located on a single scaffold in the duck genome, which is a conserved synteny group with a TRIM cluster located in the extended MHC region in chickens and turkeys. We note a TRIM27-like gene is present in ducks, and absent in chickens and turkeys. Orthologous genes are predicted in many birds and reptiles, suggesting the gene has been lost in chickens and turkeys. Using quantitative real-time PCR (qPCR) we show that TRIM27-L, and the related TRIM27.1, are upregulated 5- and 9-fold at 1 day post-infection with highly pathogenic A/Vietnam/1203/2004. To assess whether TRIM27.1 or TRIM27-L are involved in modulation of antiviral gene expression, we overexpressed them in DF1 chicken cells, and neither show any direct effect on innate immune gene expression. However, when co-transfected with duck RIG-I-N (d2CARD) to constitutively activate the MAVS pathway, TRIM27.1 weakly decreases, while TRIM27-L strongly activates innate immune signaling leading to increased transcription of antiviral genes MX1 and IFN-β. Furthermore, when both are co-expressed, the activation of the MAVS signaling pathway by TRIM27-L over-rides the inhibition by TRIM27.1. Thus, ducks have an activating TRIM27-L to augment MAVS signaling following RIG-I detection, while chickens lack both TRIM27-L and RIG-I itself.
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton AB T6G 2E9, Canada.
authors.forename: Alysson H
authors.initials: AH
authors.lastname: Blaine
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton AB T6G 2E9, Canada.
authors.forename: Domingo
authors.initials: D
authors.lastname: Miranzo-Navarro
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton AB T6G 2E9, Canada.
authors.forename: Lee K
authors.initials: LK
authors.lastname: Campbell
authors.affiliation: Division of Virology, Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
authors.forename: Jerry R
authors.initials: JR
authors.lastname: Aldridge
authors.affiliation: Division of Virology, Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Webster
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton AB T6G 2E9, Canada. Electronic address: kmagor@ualberta.ca.
authors.forename: Katharine E
authors.initials: KE
authors.lastname: Magor
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D000818:Animals; D002645:Chickens / Q000276:immunology*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004372:Ducks / Q000276:immunology*; D005585:Influenza in Birds / Q000276:immunology; D008285:Major Histocompatibility Complex / Q000276:immunology; D005810:Multigene Family; D010802:Phylogeny; D020365:RNA Helicases / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D014422:Turkeys / Q000276:immunology*; D015854:Up-Regulation / Q000235:genetics
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D020365:RNA Helicases
keywords: Avian immunology; Evolution; Influenza A; Innate immune modulation; MAVS signaling pathway; TRIM27; Tripartite-motif family