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Updated: Jun 15, 2026

Temporal Analysis of the Nuclear-to-cytoplasmic Translocation of a Herpes Simplex Virus 1 Protein by Immunofluorescent Confocal Microscopy
06:40

Temporal Analysis of the Nuclear-to-cytoplasmic Translocation of a Herpes Simplex Virus 1 Protein by Immunofluorescent Confocal Microscopy

Published on: November 4, 2018

SR proteins SRp20 and 9G8 contribute to efficient export of herpes simplex virus 1 mRNAs

Laurimar Escudero-Paunetto1, Ling Li, Felicia P Hernandez

  • 1Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA 92697, USA.

Virology
|March 16, 2010
PubMed

Insights

SR proteins SRp20 and 9G8 are crucial for efficient Herpes simplex virus 1 (HSV-1) RNA export. Depleting these SR proteins significantly reduces virus yield and causes RNA to accumulate in the nucleus.

Area of Science:

  • Virology
  • Molecular Biology
  • Cell Biology

Background:

  • Herpes simplex virus 1 (HSV-1) requires efficient mRNA export for replication.
  • The TAP/NXF1 receptor mediates viral RNA export, with ICP27 playing a key role.
  • Other export adaptors like Aly/REF have limited impact on HSV-1 RNA export.

Purpose of the Study:

  • To investigate the role of SR proteins SRp20 and 9G8 in HSV-1 RNA export.
  • To determine if SR proteins contribute to viral RNA export pathways beyond ICP27.

Main Methods:

  • Small interfering RNA (siRNA) knockdown of SRp20 and 9G8 in HSV-1 infected cells.
  • Analysis of viral RNA export efficiency via nuclear accumulation of polyadenylated (polyA+) RNA.
  • Tracking of newly transcribed RNA using Bromouridine labeling in SRp20-depleted cells.

Main Results:

  • siRNA knockdown of SRp20 or 9G8 led to a tenfold decrease in HSV-1 virus yields.
  • Depletion of SRp20 or 9G8 resulted in significant nuclear accumulation of polyA+ RNA.
  • In SRp20-depleted cells, newly transcribed RNA accumulated in the nucleus, indicating impaired export.

Conclusions:

  • SR proteins SRp20 and 9G8 are essential for efficient HSV-1 RNA export.
  • These SR proteins play a significant role in facilitating the transport of viral RNA to the cytoplasm.
  • The findings suggest a novel mechanism for viral RNA export involving SR proteins.

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