Analyses of p73 protein and mRNA in 32D/v-Abl/neo cells and 32D/v-Abl cells expressing either wild-type or truncated β4 molecules.

(A) Total cell lysates from 32D/v-Abl/neo (lane 2), 32D/v-Abl/β4 wild type (lane 3), and 32D/v-Abl/β4 L (lane 4) were analyzed by SDS-PAGE and probed with anti–p73 antibody. H-p73α, stably transduced with p73α cDNA, was used as a positive control (lane 1). (B) Total cell lysates from 32D/v-Abl/neo (lane 2), 32D/v-Abl/β4 wild type (lane 3), and 32D/v-Abl/β4 L (lane 4) were analyzed by SDS-PAGE and probed with anti–mouse p53 antibody. 32D transduced with the expression vector encoding for a p53 Val 135 was used as a positive control (lane 1). The nitrocellulose used to probe p73 and p53 proteins was stripped and probed again with the anti–tubulin antibody to normalize equal loading of proteins (lanes 2, 3, and 4). (C) Total mRNA was extracted from 32D/v-Abl/neo (lanes 1, 4, and 7), from 32D/v-Abl/β4 wild type (lanes 2, 5, and 8), and from 32D/v-Abl/β4 L (lanes 3, 6, and 9). RT-PCR analysis was performed using primers specific for mouse p73 and the housekeeping aldolase gene to amplify 2 fragments of 298 bp and 413 bp, respectively. The conditions are described in “Materials and methods.” Molecular sizes of the 2 fragments are indicated.