A Kaposi's sarcoma virus RNA element that increases the nuclear abundance of intronless transcripts

EMBO J. 2005 May 18;24(10):1831-41. doi: 10.1038/sj.emboj.7600662. Epub 2005 Apr 28.

Abstract

The Kaposi's sarcoma-associated herpesvirus produces a 1077 nucleotide noncoding, polyadenylated, exclusively nuclear RNA called PAN that is highly expressed in lytically infected cells. We report that PAN contains a novel post-transcriptional element essential for its abundant accumulation. The element, PAN-ENE (PAN RNA expression and nuclear retention element), increases the efficiency of 3'-end formation in vivo and is sufficient to enhance RNA abundance from an otherwise inefficiently expressed intronless beta-globin construct. The PAN-ENE does not concomitantly increase the production of encoded protein. Rather, it retains the unspliced beta-globin mRNA in the nucleus. Tethering of export factors can override the nuclear retention of the PAN-ENE, supporting a mechanism whereby the PAN-ENE blocks assembly of an export-competent mRNP. The activities of the PAN-ENE are specific to intronless constructs, since inserting the PAN-ENE into a spliced beta-globin construct has no effect on mRNA abundance and does not affect localization. This is the first characterization of a cis-acting element that increases RNA abundance of intronless transcripts but inhibits assembly of an export-competent mRNP.

Publication types

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

MeSH terms

  • Base Sequence
  • Cell Nucleus / metabolism*
  • Globins / biosynthesis
  • Globins / genetics
  • Herpesvirus 8, Human / genetics*
  • Herpesvirus 8, Human / metabolism
  • Humans
  • Introns
  • Molecular Sequence Data
  • Polyadenylation
  • RNA Splicing / physiology
  • RNA, Messenger / metabolism*
  • Sarcoma, Kaposi / genetics*
  • Sarcoma, Kaposi / virology
  • Transcription, Genetic / physiology

Substances

  • RNA, Messenger
  • Globins