RT Journal Article SR Electronic(1) A1 Krauer, Kenia A1 Buck, Marion A1 Flanagan, James A1 Belzer, Deanna A1 Sculley, TomYR 2004 T1 Identification of the nuclear localization signals within the Epstein–Barr virus EBNA-6 protein JF Journal of General Virology, VO 85 IS 1 SP 165 OP 172 DO https://doi.org/10.1099/vir.0.19549-0 PB Microbiology Society, SN 1465-2099, AB 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., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.19549-0