Figure 2.
PIDD-PCNA interaction is regulated in nucleus by UV-C irradiation. (a) PIDD-PCNA interaction increases in nucleus after UV-C irradiation: 293T cells were transfected with Flag-tagged PIDD, subjected to cytoplasm-nuclear fractionation as described in ‘experimental procedures', and endogenous PCNA interaction was analyzed in both fractions by anti-Flag IP after different times of 50 J/m2 UV-C irradiation. (b) Endogenous PIDD and PCNA interact in nucleus in response to UV-C irradiation: the same experiment as in figure (a) except that endogenous PIDD was immunoprecipitated. See also Supplementary Figure S2b. (c) Endogenous PIDD and PCNA interact in nucleus in a keratinocytes cell line: the same experiment as in figure (b) was performed in HaCaT cells. ([−]=IP control was done with a control IgG antibody, *=a long exposure was required to detect PIDD-FL). (b and c) The hardly detectable endogenous PIDD-FL is only detectable with really high exposure (FL*). (a–c) The p21 degradation was analysed in parallel in total extracts. Caspase-3 and lamin were used as control of cytoplasmic and nuclear extracts, respectively. Data are representative of at least three repetitions