Array-based transcript profiling and limiting-dilution reverse transcription-PCR analysis identify additional latent genes in Kaposi's sarcoma-associated herpesvirus

J Virol. 2010 Jun;84(11):5565-73. doi: 10.1128/JVI.02723-09. Epub 2010 Mar 10.

Abstract

Kaposi's sarcoma-associated herpesvirus (KSHV) is a B-lymphotropic herpesvirus strongly linked to both lymphoproliferative diseases and Kaposi's sarcoma. The viral latency program of KSHV is central to persistent infection and plays important roles in the pathogenesis of KSHV-related tumors. Up to six polypeptides and 18 microRNAs are known to be expressed in latency, but it is unclear if all major latency genes have been identified. Here, we have employed array-based transcript profiling and limiting-dilution reverse transcription-PCR (RT-PCR) methodologies to explore this issue in several KSHV-infected cell lines. Our results show that RNAs encoding the K1 protein are found at low levels in most latently infected cell lines. The gene encoding v-IL-6 is also expressed as a latent transcript in some contexts. Both genes encode powerful signaling molecules with particular relevance to B cell biology: K1 mimics signaling through the B cell receptor, and v-IL-6 promotes B cell survival. These data resolve earlier controversies about K1 and v-IL-6 expression and indicate that, in addition to core latency genes, some transcripts can be expressed in KSHV latency in a context-dependent manner.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • B-Lymphocytes / cytology
  • Cell Line
  • Gene Expression Profiling
  • Gene Expression Regulation, Viral*
  • Herpesvirus 8, Human / genetics*
  • Interleukin-6 / genetics
  • Oligonucleotide Array Sequence Analysis
  • RNA, Viral / analysis*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Viral Proteins / genetics
  • Virus Latency / genetics*

Substances

  • Interleukin-6
  • K1 protein, Human herpesvirus 8
  • RNA, Viral
  • Viral Proteins