Correlation of increased levels of Ha‐ras T24 protein with extent of loss of gap junction function in rat liver epithelial cells

Adriaan W. de Feijter, James E. Trosko, David B. Krizman, Russell M. Lebovitz, Michael W. Lieberman

Research output: Contribution to journalArticle

25 Scopus citations

Abstract

Although it is known that cells transformed by ras and other oncogenes show reduced gap junction function, to date there has been no investigation of the quantitative relationship between intracellular levels of ras oncoprotein and loss of cell-cell communication. Using the rat liver epithelial cell line MTR6, which carries a zinc-inducible metallothionein ras T24 (MTrasT24) fusion gene, we showed a direct correlation between the accumulation of ras T24 protein and the loss of dye transfer as measured by interactive laser cytometry. After stimulation with zinc sulfate, changes in both parameters were rapid and measurable by 24 h. Similarly, there was a dose-response relationship between loss of gap junction function and increase in ras T24 protein. Northern analysis of two gap junction proteins (connexins 43 and 32) showed no difference between cells that expressed high levels of ras and control cells. These data demonstrate that the degree of loss of gap junction function is dependent on the amount of increase in ras T24 protein levels, but the mechanism by which these changes are effected remains unclear.

Original languageEnglish (US)
Pages (from-to)205-212
Number of pages8
JournalMolecular Carcinogenesis
Volume5
Issue number3
DOIs
StatePublished - 1992

Keywords

  • Gap junction protein
  • Intercellular communication
  • Laser cytometry
  • Oncogene expression

ASJC Scopus subject areas

  • Cancer Research
  • Molecular Biology

Fingerprint Dive into the research topics of 'Correlation of increased levels of Ha‐ras T24 protein with extent of loss of gap junction function in rat liver epithelial cells'. Together they form a unique fingerprint.

Cite this