Skip to main content
  • Poster presentation
  • Open access
  • Published:

Molecular characterization of subcellular localization and nucleocytoplasmic shuttling of PRV UL54

Pseudorabies virus (PRV) UL54 protein localized almost exclusively to the nucleolus. By constructing a series of mutants, the putative nuclear localization signal (NLS), nucleolar localization signal (NoLS) and nuclear export signal (NES) of UL54 were for the first time mapped to amino acids 45RRRRGGRGGRAAR57, 61RQRRR65 and 240LQNLRLKLGPFL251, respectively. In addition, nuclear localization of UL54 was important for its transcriptional regulation of glycoprotein C promoter. The nuclear import of UL54 was abrogated by dominant negative RanGTP and importin β1, respectively, indicating that UL54 targeted to the nucleus by means of a classic Ran- and importin β-dependent nuclear import mechanism. Heterokaryon assays demonstrated that UL54 was a nucleocytoplasmic shuttling protein and this property could not be blocked by leptomycin B, an inhibitor of the chromosome region maintenance 1 (CRM1). However, ectopic expression of the mRNA export receptor TAP(NXF1) promoted the nuclear export of UL54 and interacted with UL54, suggesting that UL54 shuttles between the nucleus and the cytoplasm via a TAP(NXF1), but not CRM1, dependent nuclear export pathway. The present study demonstrated that UL54 is a nucleolar protein, adding UL54 to the growing list of transactivators which localize to the nucleolus and shuttle between the nucleus and the cytoplasm.

Author information

Authors and Affiliations


Rights and permissions

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and permissions

About this article

Cite this article

Li, M., Wang, S., Xing, J. et al. Molecular characterization of subcellular localization and nucleocytoplasmic shuttling of PRV UL54. BMC Proc 5 (Suppl 1), P78 (2011).

Download citation

  • Published:

  • DOI: