Open AccessThe location of endogenous wild-type p53 protein in 293T and HEK293 cells expressing low-risk HPV-6E6 fusion protein with GFP
Author(s) -
Lina Sun,
Xinxin Shen,
Yan Liu,
Ge Zhang,
Jianchun Wei,
Huijuan Zhang,
Enming Zhang,
Fengqin Ma
Publication year - 2010
Publication title -
acta biochimica et biophysica sinica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.771
H-Index - 57
eISSN - 1745-7270
pISSN - 1672-9145
DOI - 10.1093/abbs/gmq009
Subject(s) - hek 293 cells , green fluorescent protein , transfection , cytoplasm , fusion protein , biology , endogeny , microbiology and biotechnology , cell culture , suppressor , cancer research , gene , genetics , biochemistry , recombinant dna
The mechanism underlining human papillomaviruses (HPVs) causing cancer has been studied extensively, and it was concluded that the high-risk HPVs' E6 targeted and degraded tumor suppressor protein p53, leading to infected cells malignant transformation. In contrast, the low-risk HPVs only cause proliferative but non-invasive lesions of infected epithelia. Therefore, we hypothesized that low-risk HPVs' E6 might interact with p53 in a different pattern. We used a mammalian green fluorescent protein (GFP) expression system to express HPV-18E6 and HPV-6E6 fusion proteins in wild-type (wt) p53 cell lines, 293T and HEK293 cells, to investigate the traffic and location of E6s and p53. The results indicated GFP-18E6 was mainly expressed in nucleus, whereas GFP-6E6 was expressed exclusively in cytoplasm. Endogenous wt p53 was shown to be localized in the nuclei of cells transfected with GFP- 18E6. Interestingly, for the first time, we observed that p53 was trapped in the cytoplasm and never translocated into the cell nuclei transfected with GFP-6E6. In conclusion, HPV-6E6 was responsible for the cytoplasmic localization of p53. Therefore, our experiments provide a new insight into the pathogenesis of HPV.