title: PKR activation enhances replication of classical swine fever virus in PK-15 cells.
abstract: Classical swine fever (CSF) is a highly contagious swine disease that is responsible for economic losses worldwide. Protein kinase R (PK)R is an important protein in the host viral response; however, the role of PKR in CSFV infection remains unknown. This issue was addressed in the present study using the PK-15 swine kidney cell line. We found that CSFV infection increased the phosphorylation of eukaryotic translation initiation factor (eIF)2α and its kinase PKR. However, the expression of viral proteins continued to increase. Furthermore, PKR overexpression enhanced CSFV replication, while PKR inhibition resulted in reduced CSFV replication and an increase in interferon (IFN) induction. In addition, PKR was responsible for eIF2α phosphorylation in CSFV-infected cells. These results suggest that the activation of PKR during CSFV infection is beneficial to the virus. The virus is able to commandeer the host cell's translation machinery for viral protein synthesis while evading innate immune defenses.
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China.
authors.forename: Wen-Jun
authors.initials: WJ
authors.lastname: Liu
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China.
authors.forename: You-Tian
authors.initials: YT
authors.lastname: Yang
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China.
authors.forename: Ming-Qiu
authors.initials: MQ
authors.lastname: Zhao
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China.
authors.forename: Xiao-Ying
authors.initials: XY
authors.lastname: Dong
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China.
authors.forename: Hong-Chao
authors.initials: HC
authors.lastname: Gou
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China.
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Pei
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China. Electronic address: jdchen@scau.edu.cn.
authors.forename: Jin-Ding
authors.initials: JD
authors.lastname: Chen
mesh_terms: D000818:Animals; D002460:Cell Line; D006692:Classical Swine Fever Virus / Q000235:genetics / Q000502:physiology*; D004789:Enzyme Activation; D015852:Eukaryotic Initiation Factor-2 / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D005786:Gene Expression Regulation; D054884:Host-Pathogen Interactions; D010766:Phosphorylation; D013552:Swine; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism; D014779:Virus Replication; D019892:eIF-2 Kinase / Q000235:genetics / Q000378:metabolism*
chemical_list: D015852:Eukaryotic Initiation Factor-2; D014764:Viral Proteins; D019892:eIF-2 Kinase
keywords: CSFV; IFN-β; Innate immune; PKR; eIF2α