title: Probing the nuclear import signal and nuclear transport molecular determinants of PRV ICP22.
abstract: BACKGROUND
  Herpes simplex virus 1 (HSV-1) ICP22 is a multifunctional protein and important for HSV-1 replication. Pseudorabies virus (PRV) ICP22 (P-ICP22) is a homologue of HSV-1 ICP22 and is reported to be able to selectively modify the transcription of different kinetic classes of PRV genes, however, the subcellular localization, localization signal and molecular determinants for its transport to execute this function is less well understood.
  
  
  RESULTS
  In this study, by utilizing live cells fluorescent microscopy, P-ICP22 fused to enhanced yellow fluorescent protein (EYFP) gene was transient expressed in live cells and shown to exhibit a predominantly nucleus localization in the absence of other viral proteins. By transfection of a series of P-ICP22 deletion mutants fused to EYFP, a bona fide nuclear localization signal (NLS) and its key amino acids (aa) of P-ICP22 was, for the first time, determined and mapped to aa 41-60 (PASTPTPPKRGRYVVEHPEY) and aa 49-50 (KR), respectively. Besides, the P-ICP22 was demonstrated to be targeted to the nucleus via Ran-, importin α1-, and α7-mediated pathway.
  
  
  CONCLUSIONS
  Our findings reported herein disclose the NLS and molecular mechanism for nuclear transport of P-ICP22, these results will uncover new avenues for depicting the biological roles of P-ICP22 during PRV infection.
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China ; Guangzhou Hoffmann Institute of Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Mingsheng
authors.initials: M
authors.lastname: Cai
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China ; Guangzhou Hoffmann Institute of Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Si
authors.initials: S
authors.lastname: Jiang
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Zhancheng
authors.initials: Z
authors.lastname: Zeng
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Chuncong
authors.initials: C
authors.lastname: Mo
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Yanjia
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Chunke
authors.initials: C
authors.lastname: Chen
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Peiping
authors.initials: P
authors.lastname: Xie
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Bian
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Jinlin
authors.initials: J
authors.lastname: Wang
authors.affiliation: Guangdong Haid Group Co., Ltd., Guangzhou, 511400 People's Republic of China.
authors.forename: Jinlu
authors.initials: J
authors.lastname: Huang
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China ; Guangzhou Hoffmann Institute of Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Daixiong
authors.initials: D
authors.lastname: Chen
authors.affiliation: Guangzhou Hoffmann Institute of Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Peng
authors.affiliation: Department of Pathogenic Biology and Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China ; Guangzhou Hoffmann Institute of Immunology, School of Basic Science, Guangzhou Medical University, Guangzhou, 511436 People's Republic of China.
authors.forename: Meili
authors.initials: M
authors.lastname: Li
keywords: Importin; Nuclear localization signal (NLS); Nuclear transport; PRV ICP22; Ran-GTP
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