UV light affects cell membrane and cytoplasmic targets.

For a long time DNA has been regarded as the only molecular cellular target for UVB and UVC. However, evidence is accumulating that ultraviolet light (UV) can also affect cytoplasmic and membrane structures. It has been shown that UV can directly affect cytoplasmatically located transcription factors, kinases closely located to the cellular membrane and even membrane receptors. The identification of additional cellular UV targets and the mechanisms by which these targets transduce the UV signal will increase the understanding of the biological effects of UV. Recently, we observed that UV can interfere with cytokine signalling and induce apoptosis via direct activation of apoptosis-related surface receptors. These findings will be briefly reviewed in the paper.