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Updated: Jun 17, 2026

Isolation of Viral Replication Compartment-enriched Sub-nuclear Fractions from Adenovirus-infected Normal Human Cells
10:22

Isolation of Viral Replication Compartment-enriched Sub-nuclear Fractions from Adenovirus-infected Normal Human Cells

Published on: November 12, 2015

Nuclear transport of adenovirus DNA polymerase is facilitated by interaction with preterminal protein

L J Zhao1, R Padmanabhan

  • 1Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City 66103.

Cell
|December 23, 1988
PubMed

Insights

Adenovirus preterminal protein (pTP) facilitates nuclear transport of DNA polymerase (AdPol). This interaction is crucial for AdPol

Area of Science:

  • Molecular Biology
  • Virology
  • Cell Biology

Background:

  • Adenovirus mRNAs encode preterminal protein (pTP) and DNA polymerase (AdPol) from the E2B transcription unit.
  • These proteins contain main open reading frames (m-ORFs) with spliced exons.
  • Understanding protein localization and function is key to viral replication.

Purpose of the Study:

  • To investigate the functional activity and subcellular localization of adenovirus pTP and AdPol.
  • To identify the nuclear localization signals (NLS) for pTP and AdPol.
  • To determine the role of pTP-AdPol interaction in AdPol nuclear import.

Main Methods:

  • Transient expression of pTP and AdPol variants (pTP1, pTP2, AdPol1, AdPol2) in monkey kidney cells (CV1).
  • Functional assay: in vitro replication initiation.
  • Subcellular localization studies using microscopy.
  • Co-expression experiments to assess protein interactions.

Main Results:

  • Only pTP2 and AdPol2, initiated from a linker ATG, were active in replication initiation.
  • pTP (both variants) contains an NLS (RLPV(R)6VP) and is nuclear.
  • AdPol1 is cytoplasmic, while AdPol2 is localized in both cytoplasm and nucleus, suggesting its NLS is within the first 139 amino acids.
  • Co-expression of pTP and AdPol significantly increased AdPol nuclear distribution.
  • pTP facilitates AdPol nuclear transport, independent of AdPol's NLS.

Conclusions:

  • Adenovirus pTP possesses a functional nuclear localization signal.
  • Adenovirus AdPol's nuclear import is significantly enhanced by interaction with pTP.
  • pTP-mediated nuclear transport of AdPol is a critical step in adenovirus replication.

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