Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6139885 | Virology | 2014 | 6 Pages |
â¢Human adenovirus E1A is localized to the nucleus.â¢The C-terminus of E1A contains a bipartite nuclear localization signal (NLS).â¢This signal was previously misidentified to be a monopartite NLS.â¢Key basic amino acid residues within this sequence are highly conserved.
The immortalizing function of the human adenovirus 5 E1A oncoprotein requires efficient localization to the nucleus. In 1987, a consensus monopartite nuclear localization sequence (NLS) was identified at the C-terminus of E1A. Since that time, various experiments have suggested that other regions of E1A influence nuclear import. In addition, a novel bipartite NLS was recently predicted at the C-terminal region of E1A in silico. In this study, we used immunofluorescence microscopy and co-immunoprecipitation analysis with importin-α to verify that full nuclear localization of E1A requires the well characterized NLS spanning residues 285-289, as well as a second basic patch situated between residues 258 and 263 (258RVGGRRQAVECIEDLLNEPGQPLDLSCKRPRP289). Thus, the originally described NLS located at the C-terminus of E1A is actually a bipartite signal, which had been misidentified in the existing literature as a monopartite signal, altering our understanding of one of the oldest documented NLSs.