Treatment of murine 3T3 fibroblasts with mild elevated temperature (43°C for 45 minutes) followed by recovery at 37°C induced high levels of c-fos mRNA. The maximal c-fos induction was found after recovery at 37°C for 15 minutes. Sodium arsenite induced both hsp 70 and c-fos transcripts. Induction of hsp 70 and c-fos by heat shock did not require intact protein synthesis. c-fos mRNA induced by heat shock was more stable ( T1 2> 90 minutes) than that induced by phorbol esters ( t1 2∼30 minutes). Northern blot analysis in the presence of actinomycin D and nuclear run off experiments demonstrated that heat shock augmented the transcription rate of c-fos protooncogene. Human growth hormone under the control of a murine genomic c-fos fragment spanning 770 bp 5′ from the start of transcription is induced in transfected cells in response to heat shock. These data indicate that heat shock induces c-fos protooncogene acting at both transcriptional and post-transcriptional (i.e. via stabilization of transcripts) levels.
|Number of pages||7|
|Journal||Biochemical and Biophysical Research Communications|
|Publication status||Published - May 16 1990|
ASJC Scopus subject areas
- Molecular Biology