title: Ablation of Programmed -1 Ribosomal Frameshifting in Venezuelan Equine Encephalitis Virus Results in Attenuated Neuropathogenicity.
abstract: The alphaviruses Venezuelan equine encephalitis virus (VEEV), eastern equine encephalitis virus (EEEV), and western equine encephalitis virus (WEEV) are arthropod-borne positive-strand RNA viruses that are capable of causing acute and fatal encephalitis in many mammals, including humans. VEEV was weaponized during the Cold War and is recognized as a select agent. Currently, there are no FDA-approved vaccines or therapeutics for these viruses. The spread of VEEV and other members of this family due to climate change-mediated vector range expansion underscores the need for research aimed at developing medical countermeasures. These viruses utilize programmed -1 ribosomal frameshifting (-1 PRF) to synthesize the viral trans-frame (TF) protein, which has previously been shown to be important for neuropathogenesis in the related Sindbis virus. Here, the alphavirus -1 PRF signals were characterized, revealing novel -1 PRF stimulatory structures. -1 PRF attenuation mildly affected the kinetics of VEEV accumulation in cultured cells but strongly inhibited its pathogenesis in an aerosol infection mouse model. Importantly, the decreased viral titers in the brains of mice infected with the mutant virus suggest that the alphavirus TF protein is important for passage through the blood-brain barrier and/or for neuroinvasiveness. These findings suggest a novel approach to the development of safe and effective live attenuated vaccines directed against VEEV and perhaps other closely related -1 PRF-utilizing viruses.
  
  
  OBJECTIVE
  Venezuelan equine encephalitis virus (VEEV) is a select agent that has been weaponized. This arthropod-borne positive-strand RNA virus causes acute and fatal encephalitis in many mammals, including humans. There is no vaccine or other approved therapeutic. VEEV and related alphaviruses utilize programmed -1 ribosomal frameshifting (-1 PRF) to synthesize the viral trans-frame (TF) protein, which is important for neuropathogenesis. -1 PRF attenuation strongly inhibited VEEV pathogenesis in mice, and viral replication analyses suggest that the TF protein is critical for neurological disease. These findings suggest a new approach to the development of safe and effective live attenuated vaccines directed against VEEV and other related viruses.
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA.
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Kendra
authors.affiliation: National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, USA.
authors.forename: Cynthia
authors.initials: C
authors.lastname: de la Fuente
authors.affiliation: National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, USA.
authors.forename: Ashwini
authors.initials: A
authors.lastname: Brahms
authors.affiliation: National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, USA.
authors.forename: Caitlin
authors.initials: C
authors.lastname: Woodson
authors.affiliation: National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, USA.
authors.forename: Todd M
authors.initials: TM
authors.lastname: Bell
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA.
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA.
authors.forename: Yousuf A
authors.initials: YA
authors.lastname: Khan
authors.affiliation: MRIGlobal, Global Health Security, Rockville, Maryland, USA.
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Jacobs
authors.affiliation: National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, USA kkehnhal@gmu.edu dinman@umd.edu.
authors.forename: Kylene
authors.initials: K
authors.lastname: Kehn-Hall
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA kkehnhal@gmu.edu dinman@umd.edu.
authors.forename: Jonathan D
authors.identifier: http://orcid.org/0000-0002-2402-9698
authors.initials: JD
authors.lastname: Dinman
mesh_terms: D000818:Animals; D002460:Cell Line; D004666:Encephalitis Virus, Venezuelan Equine / Q000235:genetics*; D004685:Encephalomyelitis, Venezuelan Equine / Q000821:virology*; D005260:Female; D018965:Frameshifting, Ribosomal; D016679:Genome, Viral; D006736:Horses; D006801:Humans; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D012367:RNA, Viral; D014779:Virus Replication
chemical_list: D012333:RNA, Messenger; D012367:RNA, Viral
keywords: alphavirus; neuropathology; ribosomal frameshifting; vaccine; virus