Induction of micronuclei by HTLV-I Tax: a cellular assay for function

Virology. 1993 Mar;193(1):456-9. doi: 10.1006/viro.1993.1145.


Cellular chromosomal damage is ubiquitously seen in HTLV-I-transformed lymphocytes. It is also characteristic of cells that have been exposed to mutagens. A sensitive measurement for mutagen-induced DNA damage is the formation of micronuclei in treated cells. Because current evidence suggests that HTLV-I Tax is etiologically linked to transformation, we tested for its activity in inducing micronuclei. We show here that transfection into cells of a Tax-producing plasmid rapidly induced the formation of micronuclei. This effect cooperated with that of a mutagen (mitomycin C) and was correlated with the inherent trans-activation capacity of Tax. These findings suggest that a commonly used mutagen assay could be a quick biological test for putatively oncogenic proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • Cell Transformation, Viral / physiology
  • Cytopathogenic Effect, Viral
  • Gene Products, tax / physiology*
  • Human T-lymphotropic virus 1 / physiology*
  • Lymphocytes / microbiology
  • Lymphocytes / ultrastructure
  • Micronuclei, Chromosome-Defective / microbiology*


  • Gene Products, tax