Molecular anatomy of subcellular localization of HSV-1 tegument protein US11 in living cells.
The herpes simplex virus type I (HSV-1) US11 protein is an RNA-binding multifunctional regulator that specifically and stably associates with nucleoli. Although the C-terminal part of US11 was responsible for its nucleolar localization, the precise nucleolar localization signal (NoLS) and nuclear export signal (NES) of US11 and its nuclear import and export mechanisms are still elusive. In this study, fluorescence microscopy was employed to investigate the subcellular localization of US11 and characterize its transport mechanism in living cells. By constructing a series of deletion mutants fused with enhanced yellow fluorescent protein (EYFP), three novel NoLSs of US11 were for the first time mapped to amino acids 84-125, 126-152, and 89-146, respectively. Additionally, the NES was identified to locate between amino acids 89 and 119. Furthermore, the US11 protein was demonstrated to target to the cytoplasm through the NES by chromosomal region maintenance 1 (CRM1)-independent pathway, and to the nucleolus through Ran and importin beta-dependent mechanism that does not require importin alpha 5.
Xing
Junji
J
Molecular Virology and Viral Immunology Research Group, State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, 44 Xiaohongshan, Wuchang, Wuhan 430071, PR China.
Wu
Fuqing
F
Pan
Weiwei
W
Zheng
Chunfu
C
D000595:Amino Acid Sequence; D000818:Animals; D019677:Artificial Gene Fusion; D001426:Bacterial Proteins / Q000032:analysis / Q000235:genetics; D002522:Chlorocebus aethiops; D018259:Herpesvirus 1, Human / Q000235:genetics*; D008164:Luminescent Proteins / Q000032:analysis / Q000235:genetics; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D021382:Protein Sorting Signals / Q000235:genetics*; D021381:Protein Transport; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion; D014709:Vero Cells; D014764:Viral Proteins / Q000235:genetics* / Q000378:metabolism*
D001426:Bacterial Proteins; D008164:Luminescent Proteins; D021382:Protein Sorting Signals; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; C074546:US11 protein, herpesvirus; D014764:Viral Proteins; C054562:yellow fluorescent protein, Bacteria