The human endogenous retrovirus ERV-3 is upregulated in differentiating placental trophoblast cells

Virology. 1993 Oct;196(2):905-9. doi: 10.1006/viro.1993.1556.


The single copy endogenous retrovirus locus ERV-3 is known to be primarily expressed in the placenta. The absence of expression of this gene in choriocarcinoma cell lines has led to speculation that this may be a defect associated with this abnormality. We show here that ERV-3 is not normally expressed in the cytotrophoblast from which these tumour cells are derived but is expressed in normal syncytiotrophoblast. The conservation of the ERV-3 open reading frame for env in ape and old world monkey species and its tight regulation and site of expression suggest a functional role for this gene in this tissue.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Cell Differentiation
  • Cells, Cultured
  • Choriocarcinoma / microbiology
  • Female
  • Humans
  • Molecular Sequence Data
  • Pregnancy
  • Retroviridae / growth & development*
  • Trophoblasts / cytology
  • Trophoblasts / microbiology*
  • Tumor Cells, Cultured
  • Up-Regulation*