Two nuclear localization signals regulate intracellular localization of the Duck enteritis virus UL13 protein

Abstract Background UL13 multifunctional tegument protein of duck enteritis virus (DEV) is predicted as protein kinase (CHPK); however, little is known concerning its subcellular localization signal. Results In this study, by transfection with two predicted nuclear signals of DEV UL13 fused to enhanced green fluorescent protein (EGFP), two bipartite nuclear localization signal (NLS) was identified. We identified the nuclear localization signals (NLSs) that control its nuclear importing using fluorescence assay and proved that nuclear localization of DEV UL13 is a classical importin α/β-dependent process. And we constructed the mutant DEV, with the NLSs of UL13 deleted, to explore whether it will affect the replication of virus particles. Conclusions DEV UL13 protein is directed by amino acids 4 to 7 and 90 to 96, and proved that this nuclear import occurs via the classical importin α/β-dependent process. And Entry nucleus of UL13 protein has no effect on DEV replication in cell culture. Our study enhances the understanding of DEV pUL13. Taken together, these results would provide significant information for the stud y of the biological function of UL13 during DEV infection.