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Smith-McCune K, Kalman D, Robbins C, Shivakumar S, Yuschenkoff L, Bishop JMIntranuclear localization of human papillomavirus 16 E7 during transformation and preferential binding of E7 to the Rb family member p130. Proc Natl Acad Sci USA 96: 6999-7004

Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco CA 94115, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 07/1999; 96(12):6999-7004. DOI: 10.1073/pnas.96.12.6999
Source: PubMed

ABSTRACT To study intracellular pathways by which the human papillomavirus 16 oncogene E7 participates in carcinogenesis, we expressed an inducible chimera of E7 by fusion to the hormone-binding domain of the estrogen receptor. The chimeric protein (E7ER) transformed rodent fibroblast cell lines and induced DNA synthesis on addition of estradiol. In coimmunoprecipitation experiments, E7ER preferentially bound p130 when compared to p107 and pRb. After estradiol addition, E7ER localization changed to a more intense intranuclear staining. Induction of E7 function was not correlated with binding to p130 or pRb but rather with intranuclear localization and modest induction of binding to p107.

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    • "The intracellular localization of high-risk and low-risk HPV E7s and whether there are differences in location that might explain functional differences are not completely established. Using tagged HPV 16 E7 and immunofluorescence, the E7 protein was found mainly in the nucleus (Smith-McCune et al., 1999). By immunofluorescence, both untagged high-risk and low-risk HPV E7 proteins are mostly nuclear but only the low-risk HPV E7 co-localizes with PML in PML oncogenic domains (PODs) while the high-risk HPV E7 is distributed more diffusely (Guccione et al., 2002). "
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