SiRNAs do not induce RNA-dependent transcriptional silencing of retrovirus in human cells

FEBS Lett. 2007 Oct 16;581(25):4949-54. doi: 10.1016/j.febslet.2007.09.028. Epub 2007 Sep 24.

Abstract

RNA-dependent transcriptional silencing (RdTS) has been reported to operate even in human cell lines. It is tempting to speculate that RdTS plays a role in retroviral gene silencing, considering that retroviral RNA transcripts harbor a U3 promoter sequence that is a potentially good source of double-stranded RNAs. To test this possibility, we constructed several model HeLaS3 cell lines expressing GFP driven by murine leukaemia virus (MLV)-long terminal repeat (LTR) and introduced a series of shRNAs that target the U3 region of the MLV-LTR. However, transcriptional gene silencing was not induced in most instances, in spite of the fact that processed shRNA was found in cellular nuclei, indicating that RdTS does not contribute to MLV gene silencing in host cells.

MeSH terms

  • Base Sequence
  • Gene Silencing*
  • Genes, Reporter
  • Genetic Vectors
  • Green Fluorescent Proteins / analysis
  • Green Fluorescent Proteins / genetics
  • HeLa Cells
  • Humans
  • Molecular Sequence Data
  • Moloney murine leukemia virus / genetics*
  • Promoter Regions, Genetic
  • RNA, Messenger / metabolism
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • RNA, Small Interfering / physiology*
  • Terminal Repeat Sequences
  • Transcription, Genetic*
  • Tumor Suppressor Proteins / antagonists & inhibitors
  • Tumor Suppressor Proteins / genetics

Substances

  • RASSF1 protein, human
  • RNA, Messenger
  • RNA, Small Interfering
  • Tumor Suppressor Proteins
  • Green Fluorescent Proteins