Nucleolar disruption impairs Kaposi's sarcoma-associated herpesvirus ORF57-mediated nuclear export of intronless viral mRNAs

FEBS Lett. 2009 Nov 19;583(22):3549-56. doi: 10.1016/j.febslet.2009.10.040. Epub 2009 Oct 20.

Abstract

Kaposi's sarcoma-associated herpesvirus (KSHV) ORF57 plays a pivotal role in mediating the nuclear export of KSHV intronless transcripts. We demonstrate that ORF57 localises and dynamically trafficks through the nucleolus. To assess if nucleolar shuttling of ORF57 is important for the export of intronless viral mRNA, the ability of ORF57 to export mRNA was assessed in cells where the nucleolus was disrupted using Actinomycin D or DRB. We show that rapid disorganisation of the nucleolus was accompanied by a reduction in intronless virus mRNA export, suggesting that an intact nucleolus is essential for efficient KSHV ORF57-mediated intronless mRNA export.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus
  • Blotting, Western
  • Cell Line
  • Cell Nucleolus / metabolism*
  • Cell Nucleolus / virology
  • Fluorescence Recovery After Photobleaching
  • Fluorescent Antibody Technique, Indirect
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • HeLa Cells
  • Herpesvirus 8, Human / genetics
  • Herpesvirus 8, Human / metabolism*
  • Humans
  • Introns
  • RNA Transport
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism*
  • RNA, Viral / genetics
  • RNA, Viral / metabolism
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Transfection
  • Viral Proteins / genetics
  • Viral Proteins / metabolism*

Substances

  • RNA, Messenger
  • RNA, Viral
  • Recombinant Fusion Proteins
  • Viral Proteins
  • Green Fluorescent Proteins