Analysis of the cellular localization of herpes simplex virus 1 immediate-early protein ICP22.
Nuclear proteins often form punctiform structures, but the precise mechanism for this process is unknown. As a preliminary study, we investigated the aggregation of an HSV-1 immediate-early protein, infected-cell protein 22 (ICP22), in the nucleus by observing the localization of ICP22-EGFP fusion protein. Results showed that, in high-level expression conditions, ICP22-EGFP gradually concentrates in the nucleus, persists throughout the cell cycle without disaggregation even in the cell division phase, and is finally distributed to daughter cells. We subsequently constructed a mammalian cell expression system, which had tetracycline-dependent transcriptional regulators. Consequently, the location of ICP22-EGFP in the nucleus changed with distinct induction conditions. This suggests that the cellular location of ICP22 is also influenced by promoter regulation, in addition to its own structure. Our findings provide new clues for the investigation of transcriptional regulation of viral genes. In addition, the non-protease reporter system we constructed could be utilized to evaluate the role of internal ribosome entry sites (IRES) on transcriptional regulation.
Cun
Wei
W
Peking Union Medical College, Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming 650118, China.
Chen
Jie
J
Zhang
Ying
Y
Liu
Long-ding
LD
Li
Qi-han
QH
D000818:Animals; D016466:CHO Cells; D002467:Cell Nucleus / Q000737:chemistry*; D006224:Cricetinae; D003412:Cricetulus; D015967:Gene Expression Regulation, Viral; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000032:analysis / Q000235:genetics; D018259:Herpesvirus 1, Human / Q000502:physiology*; D017874:Immediate-Early Proteins / Q000032:analysis* / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000235:genetics; D013194:Staining and Labeling / Q000379:methods; D014779:Virus Replication
C057294:ICP22 protein, human herpesvirus 1; D017874:Immediate-Early Proteins; D011993:Recombinant Fusion Proteins; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins