Preferential nuclear localization of the human papillomavirus type 16 E6 oncoprotein in cervical carcinoma cells

J Gen Virol. 2003 Aug;84(Pt 8):2099-2104. doi: 10.1099/vir.0.18961-0.


The E6 protein of the high-risk human papillomavirus type 16 (HPV-16) is involved in the tumorigenesis of human cervical cells by targeting numerous cellular proteins. We characterized new anti-E6 monoclonal antibodies and used them for precise localization of the E6 oncoprotein within carcinoma cells. Overexpressed E6 protein was predominantly detected in the nucleus of transiently transfected HaCaT cells. While mostly localized at the periphery of condensed chromatin, E6 was also associated with nuclear ribonucleoproteic ultrastructures and with some ribosomal areas in the cytoplasm of SiHa and CaSki cells. The chimeric beta-galactosidase-E6 protein expressed in transfected HeLa cells was essentially localized in the nuclear compartment. Together, these data indicate that the E6 sequence of HPV-16 may encode a nuclear localization signal. The preferential nuclear distribution of this viral oncoprotein in HPV-transformed cells correlates with its activities at the transcriptional level.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Antibodies, Monoclonal / immunology*
  • Carcinoma / metabolism*
  • Cell Line
  • Cell Nucleus / metabolism*
  • Female
  • Fluorescent Antibody Technique, Indirect
  • HeLa Cells / metabolism
  • Humans
  • Microscopy, Electron
  • Molecular Sequence Data
  • Oncogene Proteins, Viral / immunology
  • Oncogene Proteins, Viral / metabolism*
  • Papillomaviridae / metabolism*
  • Repressor Proteins*
  • Transfection
  • Tumor Cells, Cultured
  • Uterine Cervical Neoplasms / metabolism*


  • Antibodies, Monoclonal
  • E6 protein, Human papillomavirus type 16
  • Oncogene Proteins, Viral
  • Repressor Proteins