The human RVB complex is required for efficient transcription of type I interferon-stimulated genes

Mol Cell Biol. 2013 Oct;33(19):3817-25. doi: 10.1128/MCB.01562-12. Epub 2013 Jul 22.

Abstract

Type I interferons (IFNs) stimulate transcription through a latent heterotrimeric transcription factor composed of tyrosine-phosphorylated STAT1 and STAT2 and the DNA binding partner IRF9, with STAT2 contributing a critical transactivation domain. Human RVB1 and RVB2, which are highly conserved AAA(+) ATP binding proteins contained in chromatin-remodeling complexes such as Ino80, SNF2-related CBP activator protein (SRCAP), and Tip60/NuA4, interacted with the transactivation domain of STAT2 in the nuclei of IFN-stimulated cells. RNA interference (RNAi) experiments demonstrated that RVB proteins were required for robust activation of IFN-α-stimulated genes (ISGs). The requirement for RVB proteins was specific to IFN-α/STAT2 signaling; transcription of tumor necrosis factor alpha (TNF-α)- and IFN-γ-driven genes was not affected by RVB1 depletion. Using RNAi-based depletion, we assessed the involvement of catalytic subunits of the RVB-containing Tip60, BRD8, Ino80, SRCAP, and URI complexes. No component other than RVB1/2 was uniquely required for ISG induction, suggesting that RVB1/2 functions as part of an as yet unidentified complex. Chromatin immunoprecipitation assays indicated that RVB1/2 was required for recruitment of RNA polymerase II (Pol II) to ISG promoters but was dispensable for STAT2 recruitment to chromatin. We hypothesize that an RVB1/2 chromatin-remodeling complex is required for efficient Pol II recruitment and initiation at ISG promoters and is recruited through interaction with the STAT2 transactivation domain.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • ATPases Associated with Diverse Cellular Activities
  • Adenosine Triphosphatases / genetics
  • Adenosine Triphosphatases / metabolism
  • Binding Sites / genetics
  • Blotting, Western
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Nucleus / drug effects
  • Cell Nucleus / genetics
  • Cell Nucleus / metabolism
  • DNA Helicases / genetics
  • DNA Helicases / metabolism*
  • DNA-Binding Proteins
  • HEK293 Cells
  • HeLa Cells
  • Histone Acetyltransferases / genetics
  • Histone Acetyltransferases / metabolism
  • Humans
  • Interferon Type I / pharmacology*
  • Lysine Acetyltransferase 5
  • Mass Spectrometry
  • Promoter Regions, Genetic / genetics
  • Protein Binding
  • RNA Interference
  • RNA Polymerase II / metabolism
  • Receptors, Thyroid Hormone / genetics
  • Receptors, Thyroid Hormone / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • STAT2 Transcription Factor / genetics
  • STAT2 Transcription Factor / metabolism
  • Transcription Factors
  • Transcription, Genetic / drug effects*

Substances

  • BRD8 protein, human
  • Carrier Proteins
  • DNA-Binding Proteins
  • Interferon Type I
  • Receptors, Thyroid Hormone
  • STAT2 Transcription Factor
  • Transcription Factors
  • Histone Acetyltransferases
  • KAT5 protein, human
  • Lysine Acetyltransferase 5
  • RNA Polymerase II
  • Adenosine Triphosphatases
  • ATPases Associated with Diverse Cellular Activities
  • DNA Helicases
  • INO80 protein, human
  • SRCAP protein, human
  • RUVBL1 protein, human
  • RUVBL2 protein, human