Cloning and expression of the cDNA for E6-AP, a protein that mediates the interaction of the human papillomavirus E6 oncoprotein with p53.
The E6 oncoproteins of the cancer-associated or high-risk human papillomaviruses (HPVs) target the cellular p53 protein. The association of E6 with p53 leads to the specific ubiquitination and degradation of p53 in vitro, suggesting a model by which E6 deregulates cell growth control by the elimination of the p53 tumor suppressor protein. Complex formation between E6 and p53 requires an additional cellular factor, designated E6-AP (E6-associated protein), which has a native and subunit molecular mass of approximately 100 kDa. Here we report the purification of E6-AP and the cloning of its corresponding cDNA, which contains a novel open reading frame encoding 865 amino acids. E6-AP, translated in vitro, has the following properties: (i) it associates with wild-type p53 in the presence of the HPV16 E6 protein and simultaneously stimulates the association of E6 with p53, (ii) it associates with the high-risk HPV16 and HPV18 E6 proteins in the absence of p53, and (iii) it induces the E6- and ubiquitin-dependent degradation of p53 in vitro.
Pubmed ID: 8380895 RIS Download
Amino Acid Sequence | Animals | Base Sequence | Cloning, Molecular | DNA, Viral | Humans | Molecular Sequence Data | Oncogene Proteins, Viral | Papillomaviridae | Protein Biosynthesis | Rats | Repressor Proteins | Sequence Homology, Amino Acid | Tumor Suppressor Protein p53 | Ubiquitin-Protein Ligases | Viral Proteins