Fig. 2. Analysis of gene expression. Total RNA was analyzed by northern blot. Transfers were stripped and probed for the expression of gapdh to assess loading. Results from two representative experiments are shown. (A) Gene expression in wild-type and p130/p107-null MEFs. MEFs were treated with adriamycin (345 nM) and northern blots were analyzed with the probes indicated. (B) Repression by p53. The effect of p53 was determined using (10)1 Val5 cells with a temperature-sensitive p53. p53-null MEFs were used as a control.