Cloned mouse mammary tumor virus DNA is biologically active in transfected mouse cells and its expression is stimulated by glucocorticoid hormones

Cell. 1981 Feb;23(2):335-45. doi: 10.1016/0092-8674(81)90129-x.

Abstract

We have cloned circular unintegrated mouse mammary tumor virus (MMTV) DNA from infected rat hepatoma cells in bacteriophage lambda. Seven independent clones containing MMTV DNA of homogeneous length of 9 kb (five) or 10 kb (two) were identified. The five 9 kb clones had identical restriction maps consistent with that of 9 kb unintegrated DNA; the other two were aberrant. MMTV DNA inserts were purified, ligated and used for cotransfection of Ltk- cells together with a plasmid containing the thymidine kinase gene of herpes simplex virus. All Tk+ cell clones acquired new MMTV sequences and those transfected with the 9 kb MMTV DNA synthesized normal viral RNA and proteins. Viral gene expression was increased by the addition of dexamethasone.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Cloning, Molecular*
  • DNA Restriction Enzymes
  • DNA, Viral / analysis
  • Dexamethasone / pharmacology*
  • Gene Expression Regulation / drug effects*
  • Mammary Tumor Virus, Mouse / genetics*
  • Mice
  • RNA, Viral / analysis
  • Transfection*
  • Viral Proteins / biosynthesis

Substances

  • DNA, Viral
  • RNA, Viral
  • Viral Proteins
  • Dexamethasone
  • DNA Restriction Enzymes