Cotranslation of Activated Mutant P53 with Wild Type Drives the Wild-type P53 Protein into the Mutant Conformation

Activating mutations of p53 promote tumor progression. The mutant protein adopts a characteristic conformation, which lacks the growth suppressor function of wild-type p53. We show that mutant p53 can drive cotranslated wild-type p53 into the mutant conformation: a similar effect in vivo would block wild-type suppressor function with dominant negative effect. The cotranslational effect of mutant p53 on wild-type conformation depends upon interaction between nascent polypeptides and oligomerization of the full-length proteins. We also show that oligomers of p53 proteins can be induced to change conformation in a cooperative manner. Cell growth stimulation induces a similar conformational change in p53, and our present results indicate that this may involve allosteric regulation.