Fig. 4.
Expression levels of p21CIP.(A) Northern blot analysis with p21CIP- and GAPDH-specific probes. HeLa cells were infected with empty Ad and AdE2ts followed by temperature shift as described in the Fig. 3 legend. Lanes 1 and 2 represent samples infected with empty Ad at 32°C and 39.5°C, and lanes 3 and 4 represent samples infected with AdE2ts at 32°C and 39.5°C. Blots hybridized with p21CIP probe were stripped and reprobed with GAPDH for normalization. (B) Normalized p21CIP values from A are represented relative to the Ad sample at 32°C and are compared with the data from three independent microarray experiments. (C) HeLa cells were infected as in A, protein extracts were prepared on day 3 postsenescence induction, and equal amounts of proteins were subjected to Western blot analysis by using p53- and p21CIP-specific antibodies.