%0 Journal Article %A Krauer, Kenia %A Buck, Marion %A Flanagan, James %A Belzer, Deanna %A Sculley, Tom %T Identification of the nuclear localization signals within the Epstein–Barr virus EBNA-6 protein %D 2004 %J Journal of General Virology, %V 85 %N 1 %P 165-172 %@ 1465-2099 %R https://doi.org/10.1099/vir.0.19549-0 %I Microbiology Society, %X Epstein–Barr virus nuclear antigen (EBNA)-6 is essential for EBV-induced immortalization of primary human B-lymphocytes in vitro. Previous studies have shown that EBNA-6 acts as a transcriptional regulator of viral and cellular genes; however at present, few functional domains of the 140 kDa EBNA-6 protein have been completely characterized. There are five computer-predicted nuclear localization signals (NLS), four monopartite and one bipartite, present in the EBNA-6 amino acid sequence. To identify which of these NLS are functional, fusion proteins between green fluorescent protein and deletion constructs of EBNA-6 were expressed in HeLa cells. Each of the constructs containing at least one of the NLS was targeted to the nucleus of cells whereas a construct lacking all of the NLS was cytoplasmic. Site-directed mutation of these NLS demonstrated that only three of the NLS were functional, one at the N-terminal end (aa 72–80), one in the middle (aa 412–418) and one at the C-terminal end (aa 939–945) of the EBNA-6 protein. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.19549-0