ABSTRACT
The synthesis of a protein can be influenced on many levels, such as the rate of transcription, the stability of the messenger RNA, or the rate of translation of the messenger. In most cases examined, both phorbol esters and ultraviolet irradiation (UV) increased the transcription of the respective genes. The expression of several genes is activated by both agents: for example, genes coding for transcription factors and replication factor, as well as genes coding for growth factors and for secreted proteases. The interest in the UV-induced genetic response in mammalian cells is catching up. Besides induction of expression of specific genes, another common consequence of treatment of cells with UV or with tumor promoters is an “attempt” to proliferate. The UV pushes quiescent primary human fibroblasts into a round of DNA synthesis similar to the one induced by growth factors.
