Figure 1.

Association of MDM2 with p300 and p53 in the nucleus. (A) Purification of the MDM2-associated complex from HeLa nuclear extracts. The MDM2-associated protein complex was purified from human HeLa nuclear extracts through chromatography as described in Materials and Methods. Fractions (25 μl) from the last Superdex 200 column were analyzed on SDS/PAGE, followed by WB by using antibodies against p300 (Upper), MDM2, and p53, respectively, in this order. Molecular weight markers at the top of A indicate the fractions where corresponding size markers coeluted. Fraction 18 was analyzed on SDS/PAGE and by silver staining, as shown in B.