Figure 1.

Reconstitution of the polyubiquitination of p53. A, reactions were performed under standard conditions, and the products were visualized by Western blotting with the indicated antibodies. For E2s, 5 and 7 indicate UBCH5c and UBCH7, respectively. B, formation of the thiol linkage between E6AP and Ub (E6AP∼Ub) in the presence or absence of E6. E3-charging assays were performed as described under “Experimental procedures,” and the products were analyzed under nonreducing or reducing conditions by Western blotting with anti-E6AP antibody.