Skip to main content
. 1998 Mar 17;95(6):2834–2837. doi: 10.1073/pnas.95.6.2834

Figure 5.

Figure 5

p53 bound to DNA is immunoprecipitated by Ab389. (a) Nuclear extracts (NE) were prepared from UV-treated and untreated rat embryo fibroblasts, and DNA-binding assays were performed as described (20). Extracts from untreated (lanes 3, 5, and 7) and UV-treated cells (lanes 4, 6, and 8) were incubated with the radiolabeled DNA containing the p21 promoter (20) for 30 min at 4°C. DNA-protein complexes were immunoprecipitated by either pAb248 (lanes 3 and 4), Ab389 (lanes 5 and 6), or pAb421 (lanes 7 and 8), and the bound DNA was analyzed on 5% nondenaturing polyacrylamide gel followed by autoradiography. Lanes 1 and 2 contain free probe and no nuclear extract, respectively. (b) Bacterially expressed p53 was phosphorylated in vitro with CK II (as described in Fig. 3). Untreated and phosphorylated extracts were used for DNA-binding assays as described above. Immunoprecipitations were performed with pAb248 (lanes 3 and 4) or Ab389 (lanes 5 and 6), and bound DNA was analyzed as above. Lanes 1 and 2 contain free probe and no nuclear extract, respectively.