Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Virol. 2013 May;87(9):5255-69. doi: 10.1128/JVI.03575-12. Epub 2013 Feb 28.

H2AX phosphorylation is important for LANA-mediated Kaposi's sarcoma-associated herpesvirus episome persistence.

Author information

  • 1Department of Microbiology and Tumor Virology Program, Abramson Comprehensive Cancer Center, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.

Abstract

The DNA damage response (DDR) of host cells is utilized by a number of viruses to establish and propagate their genomes in the infected cells. We examined the expression of the DDR genes during Kaposi's sarcoma-associated herpesvirus (KSHV) infection of human peripheral blood mononuclear cells (PBMCs). The genes were mostly downregulated, except H2AX, which was upregulated during infection. H2AX is important for gammaherpesvirus infectivity, and its phosphorylation at serine 139 is crucial for maintenance of latency during mouse gamma-herpesvirus 68 (MHV-68) infection. We now also observed phosphorylation of H2AX at serine 139 during KSHV infection. H2AX is a histone H2A isoform shown to interact with the latency-associated nuclear antigen (LANA) encoded by KSHV. Here, we show that LANA directly interacted with H2AX through domains at both its N and C termini. The phosphorylated form of H2AX (γH2AX) was shown to colocalize with LANA. Chromatin immunoprecipitation (ChIP) assays showed that a reduction in H2AX levels resulted in reduced binding of LANA with KSHV terminal repeats (TRs). Binding preferences of H2AX and γH2AX along the KSHV episome were examined by whole-episome ChIP analysis. We showed that γH2AX had a higher relative binding activity along the TR regions than that of the long unique region (LUR), which highlighted the importance of H2AX phosphorylation during KSHV infection. Furthermore, knockdown of H2AX resulted in decreased KSHV episome copy number. Notably, the C terminus of LANA contributed to phosphorylation of H2AX. However, phosphorylation was not dependent on the ability of LANA to drive KSHV-infected cells into S-phase. Thus, H2AX contributes to association of LANA with the TRs, and phosphorylation of H2AX is likely important for its increased density at the TRs.

PMID:
23449797
[PubMed - indexed for MEDLINE]
PMCID:
PMC3624323
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk