Dual functions of rift valley fever virus NSs protein: Inhibition of host mRNA transcription and post-transcriptional downregulation of protein kinase PKR

Tetsuro Ikegami, Krishna Narayanan, Sungyong Won, Wataru Kamitani, C. J. Peters, Shinji Makino

Research output: Contribution to journalReview article

55 Scopus citations

Abstract

Rift Valley fever virus (RVFV), which belongs to the genus Phlebovirus, family Bunyaviridae, is a negative-stranded RNA virus carrying a single-stranded, tripartite RNA genome. RVFV is an important zoonotic pathogen transmitted by mosquitoes and causes large outbreaks among ruminants and humans in Africa and the Arabian Peninsula. Human patients develop an acute febrile illness, followed by a fatal hemorrhagic fever, encephalitis, or ocular diseases. A viral nonstructural protein, NSs, is a major viral virulence factor. Past studies showed that NSs suppresses the transcription of host mRNAs, including interferon-β mRNAs. Here we demonstrated that the NSs protein induced post-transcriptional downregulation of dsRNA-dependent protein kinase (PKR), to prevent phosphorylation of eIF2α and promoted viral translation in infected cells. These two biological activities of the NSs most probably have a synergistic effect in suppressing host innate immune functions and facilitate efficient viral replication in infected mammalian hosts.

Original languageEnglish (US)
Pages (from-to)E75-E85
JournalAnnals of the New York Academy of Sciences
Volume1171
Issue numberSUPPL. 1
DOIs
StatePublished - Sep 2009

Keywords

  • NSs protein
  • PKR
  • Rift Valley fever virus
  • interferon
  • transcriptional suppression

ASJC Scopus subject areas

  • Neuroscience(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • History and Philosophy of Science

Fingerprint Dive into the research topics of 'Dual functions of rift valley fever virus NSs protein: Inhibition of host mRNA transcription and post-transcriptional downregulation of protein kinase PKR'. Together they form a unique fingerprint.

  • Cite this