Preferential induction of c-fos versus c-jun protooncogene during the immediate early response of pig skin to gamma-rays.

The involvement of the nuclear protooncogenes c-fos and c-jun in the immediate early response of pig dermis cells was studied after in vivo gamma-irradiation. Following high radiation doses (8 to 48 Gy), the two protooncogenes were concomitantly induced, although c-fos induction was preferential. Both inductions were time and dose dependent. Therefore, the early response of the skin to high doses of radiation might involve heterodimeric activator protein 1 composed of c-Fos and c-Jun proteins. Following low radiation doses (0.5 to 2 Gy), c-jun was not induced. By contrast, dramatic c-fos induction was observed after 0.5 Gy, suggesting a specific role for c-fos at low doses.