Figure 6.

Analysis of p53, Arf, and Mdm2 status in Ksr1−/− Eμ-myc lymphomas. (a) Southern blot for Arf in lymphomas from Ksr−/− Eμ-myc transgenic mice where Arf was not detectable by western blot. Lymphomas that had biallelic Arf deletion are denoted by an asterisk (^*). Control DNA for wild-type (WT) Arf loci and biallelic Arf deletion (del) are indicated. (b) Protein lysates of lymphomas from Ksr1−/− Eμ-myc transgenic mice were western blotted for p53, Arf, Mdm2, and as a loading control, β-actin. Lysates from lymphomas that overexpress Mdm2 and Arf or mutant p53 and p53-null MEFs are controls. An asterisk (^*) denotes lymphomas with mutant p53 as determined by sequencing. The percentage of lymphomas that contained the indicated alterations is shown