Differential effects of UV-B and UV-C components of solar radiation on MAP kinase signal transduction pathways in epidermal keratinocytes.
Exposure to solar ultraviolet (UV) light is a major cause of skin cancer, the most common human neoplasm. The earth's upper atmosphere absorbs the high energy UV-C wavelengths (100-280 nm), while allowing transmission of UV-B (280-320 nm) and UV-A (320-400 nm). It is therefore UV-B and to some extent UV-A, that contributes to most human skin malignancies. We report that the exposure of cultured keratinocytes or skin to UV-C radiation causes activation of MAP kinases (ERK and JNK). In contrast, the solar radiation associated with skin cancer (UV-B) was an ineffective activator of the ERK and JNK signal transduction pathways. Therefore, while exposure of epidermal cells to UV-C radiation under laboratory conditions causes marked activation of MAP kinase signal transduction pathways, only a low level of MAP kinase signaling is involved in the response of skin to biologically relevant solar radiation.
D000818:Animals; D016466:CHO Cells / Q000201:enzymology / Q000528:radiation effects; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000096:biosynthesis / Q000378:metabolism / Q000528:radiation effects*; D002478:Cells, Cultured; D006224:Cricetinae; D004789:Enzyme Activation / Q000528:radiation effects; D004790:Enzyme Induction / Q000528:radiation effects; D005260:Female; D005786:Gene Expression Regulation; D011905:Genes, ras; D048031:JNK Mitogen-Activated Protein Kinases; D015603:Keratinocytes / Q000201:enzymology / Q000528:radiation effects*; D051379:Mice; D008812:Mice, Hairless; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D011505:Protein-Tyrosine Kinases / Q000378:metabolism / Q000528:radiation effects; D015398:Signal Transduction / Q000528:radiation effects*; D012867:Skin / Q000201:enzymology / Q000528:radiation effects; D014466:Ultraviolet Rays / Q000009:adverse effects*; D018631:ras Proteins / Q000096:biosynthesis / Q000235:genetics
D011505:Protein-Tyrosine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D018631:ras Proteins