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Basic Characteristics of Mutations
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Mutation Site
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F47R |
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Mutation Site Sentence
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The E6 F47R mutant is defective for polyubiquitination and subsequent degradation of p53. |
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Mutation Level
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Amino acid level |
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Mutation Type
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Nonsynonymous substitution |
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Gene/Protein/Region
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E6 |
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Standardized Encoding Gene
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E6
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Genotype/Subtype
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HPV16 |
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Viral Reference
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-
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Functional Impact and Mechanisms
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Disease
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Uterine Cervical Neoplasms
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Immune
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- |
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Target Gene
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TP53
MDM2
CDKN1A
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Clinical and Epidemiological Correlations
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Clinical Information
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- |
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Treatment
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- |
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Location
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- |
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Literature Information
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PMID
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19015633
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Title
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A single-codon mutation converts HPV16 E6 oncoprotein into a potential tumor suppressor, which induces p53-dependent senescence of HPV-positive HeLa cervical cancer cells
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Author
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Ristriani T,Fournane S,Orfanoudakis G,Trave G,Masson M
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Journal
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Oncogene
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Journal Info
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2009 Feb 5;28(5):762-72
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Abstract
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High-risk mucosal human papillomaviruses (HPV), mainly HPV16 and HPV18, are implicated in cervical carcinogenesis. HPV16 E6 oncoprotein binds and often targets for degradation numerous cell proteins, including the tumor suppressor p53 and several PDZ domain proteins. Here, we show that a single-point mutation, F47R, is sufficient to convert the HPV16 E6 oncoprotein into a suppressor of HPV-positive HeLa cervical cancer cells proliferation. The E6 F47R mutant is defective for polyubiquitination and subsequent degradation of p53. When expressed in HPV-positive cervical cancer cells, E6 F47R acts as a dominant negative mutant by counteracting the p53 degradation activity of endogenous E6 and restoring high p53 protein levels. Moreover, the prolonged expression of E6 F47R leads to suppression of HeLa cells proliferation through the induction of premature senescence. This phenotype is independent on the PDZ-binding activity of E6. F47R-senescent HeLa cells exhibit a sustained expression of p53, hMDM2 and p21(CIP) proteins and a reduced expression of endogenous HPV18 E6 protein. Finally, small interfering RNAs directed against p53 counteract the effect of E6 F47R expression, indicating that E6 F47R-induced cellular senescence is strongly dependent on p53 signaling pathway.
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Sequence Data
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-
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