UVC induced translocation of protein kinase C (PKC) and expression change of c-myc oncogene in human skin keratinocytes / 대한해부학회지

ABSTRACT

Recent studies have documented that UVC induced DNA damage leads to activation of protein kinase C (PKC) isoforms, which result in the transient expression of immediate early gene expression, then in phosphorylation of p53, its nuclear accumulation, and the cascade which leads to DNA repair, apoptosis, or carcinogenesis. But long-term activations and translocations of PKC isoforms were found after recovery of expression of one of immediate early gene, c-myc. Three days later after UVC 5 J/m2 irradiation, PKCalpha and beta molecules were shifted to around nuclei from even distribution in cytosol. Multiple irradiation of UVC (5 J/m2 for 5 times) induced more consolidated translocation of PKC alpha, while up-regulation and translocation of PKCbeta expression was responded with single does. PKCgamma molecule was basically accumulated around nuclear membrane. UVC irradiation caused a transient increase of membrane fraction of PKCgamma with single dose. These results suggest that UVC induced long-term activation of PKC after recovery of c-myc gene expression results from the translocation of PKC isoforms of cytosol to nuclear membrane or around nucleus rather than translocation to cell membrane. These intracellular shift of PKC molecules after 3 days might be not associated with c-myc expression.