Structural basis underlying viral hijacking of a histone chaperone complex

Nat Commun. 2016 Sep 1:7:12707. doi: 10.1038/ncomms12707.

Abstract

The histone H3.3 chaperone DAXX is implicated in formation of heterochromatin and transcription silencing, especially for newly infecting DNA virus genomes entering the nucleus. Epstein-Barr virus (EBV) can efficiently establish stable latent infection as a chromatinized episome in the nucleus of infected cells. The EBV tegument BNRF1 is a DAXX-interacting protein required for the establishment of selective viral gene expression during latency. Here we report the structure of BNRF1 DAXX-interaction domain (DID) in complex with DAXX histone-binding domain (HBD) and histones H3.3-H4. BNRF1 DID contacts DAXX HBD and histones through non-conserved loops. The BNRF1-DAXX interface is responsible for BNRF1 localization to PML-nuclear bodies typically associated with host-antiviral resistance and transcriptional repression. Paradoxically, the interface is also required for selective transcription activation of viral latent cycle genes required for driving B-cell proliferation. These findings reveal molecular details of virus reprogramming of an antiviral histone chaperone to promote viral latency and cellular immortalization.

Publication types

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

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism*
  • B-Lymphocytes / immunology
  • Cell Line
  • Cell Nucleus / metabolism
  • Cell Proliferation / genetics
  • Chromatin Assembly and Disassembly / genetics
  • Co-Repressor Proteins
  • HEK293 Cells
  • Herpesvirus 4, Human / genetics*
  • Histone Chaperones / metabolism*
  • Histones / metabolism*
  • Humans
  • Molecular Chaperones
  • Nuclear Proteins / metabolism*
  • Protein Binding / genetics
  • Protein Domains
  • Viral Envelope Proteins / metabolism*
  • Virus Latency / genetics

Substances

  • Adaptor Proteins, Signal Transducing
  • Co-Repressor Proteins
  • DAXX protein, human
  • Histone Chaperones
  • Histones
  • Molecular Chaperones
  • Nuclear Proteins
  • P140 protein, Epstein-barr virus
  • Viral Envelope Proteins