[Epstein-Barr virus latent membrane protein 1 induces the telomerase activity in human nasopharyngeal epithelial cells].
Telomerase activation has been linked to cell immortalization in vitro and tumorigenicity in vivo. In this study, for the first, we reported that Epstein-Barr virus activated the telomerase activity of human nasopharyngeal epithelial cells in the early stage of immortalization as tested by the PCR-ELISA. The telomerase activity in nasopharyngeal epithelial cells was only observed in presenescent cells. It was implicated that Epstein-Barr virus induced the escape of nasopharyngeal epithelial cells from senescence via the activation of telomerase. We further showed that telomerase activation in infected cells was dependent on the protein level of latent membrane protein 1 (LMP1) encoded by Epstein-Barr virus using a Tetracycline regulatory cell line expressing LMP1, pTet-on-LMP1-HNE2. The activity of telomerase in nasopharyngeal cells was decreased when the protein level of LMP1 was blocked by antisense LMP1 plasmid DNA. And the activity of telmerase was also related to the carboxyl terminus of LMP1. It was implicated that the ability of Epstein-Barr virus to suppress senescence is associated with telomerase activation by LMP1.
Yang
J
J
Cancer Research Institute, Hunan Medical University, Changsha Hunan, 410078.
Deng
X Y
XY
Gu
H H
HH
Xia
L Q
LQ
Yi
W
W
Cao
Y
Y
D002472:Cell Transformation, Viral; D002478:Cells, Cultured; D016922:Cellular Senescence; D004847:Epithelial Cells / Q000201:enzymology* / Q000821:virology; D004854:Herpesvirus 4, Human / Q000502:physiology*; D006801:Humans; D009305:Nasopharynx / Q000166:cytology* / Q000201:enzymology / Q000821:virology; D019098:Telomerase / Q000378:metabolism*; D014763:Viral Matrix Proteins / Q000502:physiology*
C037662:EBV-associated membrane antigen, Epstein-Barr virus; D014763:Viral Matrix Proteins; D019098:Telomerase