DRBP76 associates with Ebola virus VP35 and suppresses viral polymerase function

J Infect Dis. 2011 Nov;204 Suppl 3(Suppl 3):S911-8. doi: 10.1093/infdis/jir343.

Abstract

The Zaire Ebola virus (EBOV) protein VP35 is multifunctional; it inhibits IFN-α/β production and functions as a cofactor of the viral RNA polymerase. Mass spectrometry identified the double stranded RNA binding protein 76 (DRBP76/NFAR-1/NF90) as a cellular factor that associates with the VP35 C-terminal interferon inhibitory domain (IID). DRBP76 is described to regulate host cell protein synthesis and play an important role in host defense. The VP35-IID-DRBP76 interaction required the addition of exogenous dsRNA, but full-length VP35 associated with DRBP76 in the absence of exogenous dsRNA. Cells infected with a Newcastle disease virus (NDV)-expressing VP35 redistributed DRBP76 from the nucleus to the cytoplasm, the compartment in which EBOV replicates. Overexpression of DRBP76 did not alter the ability of VP35 to inhibit type I IFN production but did impair the function of the EBOV transcription/replication complex. These data suggest that DRBP76, via its association with VP35, exerts an anti-EBOV function.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chlorocebus aethiops
  • DNA-Directed RNA Polymerases / genetics
  • DNA-Directed RNA Polymerases / metabolism*
  • Ebolavirus / physiology*
  • Gene Expression Regulation / physiology*
  • HEK293 Cells
  • Humans
  • Interferon-beta / genetics
  • Interferon-beta / metabolism
  • Newcastle disease virus / genetics
  • Nuclear Factor 90 Proteins / genetics
  • Nuclear Factor 90 Proteins / metabolism*
  • Poly I-C
  • Promoter Regions, Genetic
  • Protein Structure, Tertiary
  • RNA, Double-Stranded
  • Vero Cells
  • Viral Regulatory and Accessory Proteins / genetics
  • Viral Regulatory and Accessory Proteins / metabolism*
  • Virus Replication

Substances

  • ILF3 protein, human
  • Nuclear Factor 90 Proteins
  • RNA, Double-Stranded
  • VP35 protein, filovirus
  • Viral Regulatory and Accessory Proteins
  • Interferon-beta
  • DNA-Directed RNA Polymerases
  • Poly I-C