Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Apoptosis and Delayed Expression of c-jun and c-fos after Gamma Irradiation of Jurkat T Cells

Randi G. Syljuåsen, Ji-Hong Hong and William H. McBride
Radiation Research
Vol. 146, No. 3 (Sep., 1996), pp. 276-282
DOI: 10.2307/3579457
Stable URL: http://www.jstor.org/stable/3579457
Page Count: 7
  • Read Online (Free)
  • Download ($10.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Apoptosis and Delayed Expression of c-jun and c-fos after Gamma Irradiation of Jurkat T Cells
Preview not available

Abstract

The purpose of this study was to determine the role of radiation-induced expression of c-jun and c-fos in radiation-induced apoptosis of cells of the Jurkat T-cell line. Doses of 10-20 Gy caused a massive number of cells to undergo apoptosis within the first 24 h. This was accompanied by extensive increases in c-jun mRNA levels and moderate increases in c-fos levels, both occurring at the time of onset of internucleosomal DNA fragmentation. Increased c-jun and c-fos expression was maximum at 8 h after irradiation with a 10-fold increase in c-jun and a 2-fold increase in c-fos mRNA levels. In comparison, stimulation of the Jurkat cells with PMA resulted in rapid induction of c-jun and c-fos within 1 h. The late induction of c-jun and c-fos was not preceded by induction of tumor necrosis factor-α (TNF-α) or the bifunctional repair endonuclease and nuclear redox factor Ref-1; rather a slow decrease in Ref-1 mRNA levels was found over the first 24 h. Our results showed that radiation-induced c-jun and c-fos expression is a late response in Jurkat cells, and is most likely a secondary effect not necessary for radiation-induced apoptosis. Furthermore, apoptosis was induced by the RNA synthesis inhibitor actinomycin D, which does not induce c-jun or c-fos expression. This demonstrates that massive late induction of c-jun and c-fos is not a general requirement for apoptosis in Jurkat cells.

Page Thumbnails

  • Thumbnail: Page 
276
    276
  • Thumbnail: Page 
277
    277
  • Thumbnail: Page 
278
    278
  • Thumbnail: Page 
279
    279
  • Thumbnail: Page 
280
    280
  • Thumbnail: Page 
281
    281
  • Thumbnail: Page 
282
    282