title: Human cytomegalovirus TRS1 protein associates with the 7-methylguanosine mRNA cap and facilitates translation.
abstract: Viruses rely on the host translation machinery for the synthesis of viral proteins. Human cells have evolved sensors that recognize viral RNAs and inhibit mRNA translation in order to limit virus replication. Understanding how viruses manipulate the host translation machinery to gain access to ribosomes and disable the antiviral response is therefore a critical aspect of the host/pathogen interface. In this study, we used a proteomics approach to identify human cytomegalovirus (HCMV) proteins that might contribute to viral mRNA translation. The HCMV TRS1 protein (pTRS1) associated with the 7-methylguanosine mRNA cap, increased the total level of protein synthesis, and colocalized with mRNAs undergoing translation initiation during infection. pTRS1 stimulated translation of a nonviral reporter gene and increased the translation of a reporter containing an HCMV 5' untranslated region (5'UTR) to a greater extent. The preferential effect of pTRS1 on translation of an mRNA containing a viral 5'UTR required the pTRS1 RNA and double-stranded RNA-dependent protein kinase (PKR)-binding domains, and was likely the result of PKR inhibition. However, pTRS1 also stimulated the total level of protein synthesis and translation directed by an HCMV 5'UTR in cells lacking PKR. Thus our results demonstrate that pTRS1 stimulates translation through both PKR-dependent and PKR-independent mechanisms.
authors.affiliation: Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Ziehr
authors.affiliation: Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Erik
authors.initials: E
authors.lastname: Lenarcic
authors.affiliation: Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Heather A
authors.initials: HA
authors.lastname: Vincent
authors.affiliation: Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.|North Carolina Department of Agriculture, Rollins Animal Disease Diagnostic Lab, Raleigh, NC, USA.
authors.forename: Chad
authors.initials: C
authors.lastname: Cecil
authors.affiliation: Department of Molecular Biology, Princeton University, Princeton, NJ, USA.|Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Garcia
authors.affiliation: Department of Molecular Biology, Princeton University, Princeton, NJ, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Shenk
authors.affiliation: Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Nathaniel J
authors.initials: NJ
authors.lastname: Moorman
mesh_terms: D015153:Blotting, Western; D002478:Cells, Cultured; D003587:Cytomegalovirus / Q000502:physiology*; D003586:Cytomegalovirus Infections / Q000378:metabolism* / Q000821:virology; D005347:Fibroblasts / Q000378:metabolism / Q000821:virology; D015967:Gene Expression Regulation, Viral; D006151:Guanosine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D047468:Immunoprecipitation; D014176:Protein Biosynthesis; D039381:RNA Cap-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D012367:RNA, Viral / Q000235:genetics; D012270:Ribosomes / Q000378:metabolism; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication
chemical_list: D039381:RNA Cap-Binding Proteins; D012333:RNA, Messenger; D012367:RNA, Viral; C072216:TRS1 protein, Human herpesvirus 5; D014764:Viral Proteins; D006151:Guanosine; C016578:7-methylguanosine
keywords: Microbiology; PKR; Translational control; Virology