NS1' protein expression facilitates production of Japanese encephalitis virus in avian cells and embryonated chicken eggs.
Japanese encephalitis virus (JEV), which belongs to the genus Flavivirus of the family Flaviviridae, is a leading cause of meningo-encephalitis in Asian countries. The flavivirus non-structural protein 1 (NS1) plays a role in virus replication and in the elicitation of an immune response. The NS1' protein found among the members of the JEV subgroup is an extended form of NS1 and is generated by a -1 ribosomal frameshift. This protein is known to be involved in viral pathogenicity; however, its specific function is still unknown. Here, we describe an investigation of the molecular function of NS1' protein through the production of JEV NS1'-expressing and -non-expressing clones and their infection of avian and mammalian cells. Efficient NS1' protein expression was observed in avian cells and was found to facilitate JEV production in both avian cultured cells and embryonated chicken eggs. NS1' protein was observed to co-localize with NS5 protein and resulted in increased viral RNA levels in avian cells. These findings clearly indicate that NS1' enhances the production of JEV in avian cells and may facilitate the amplification/maintenance role of birds in the virus transmission cycle in nature.
Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.|Department of Virology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
Yuki
Y
Takamatsu
Department of Virology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
Kenta
K
Okamoto
Respiratory Viruses Laboratory, Department of Virology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam.|Department of Virology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
Duc Tuan
DT
Dinh
Department of Virology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
Fuxun
F
Yu
Department of Virology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
Daisuke
D
Hayasaka
Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.|Department of Virology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
Leo
L
Uchida
Department of Virology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
Takeshi
T
Nabeshima
Department of Molecular Epidemiology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.|Department of Virology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
Corazon C
CC
Buerano
Department of Virology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
Kouichi
K
Morita
D000818:Animals; D001717:Birds; D002460:Cell Line; D002642:Chick Embryo; D002645:Chickens; D004664:Encephalitis Virus, Japanese / Q000254:growth & development*; D017361:Viral Nonstructural Proteins / Q000096:biosynthesis* / Q000378:metabolism
C100315:NS1 protein, Flavivirus; C096041:NS5 protein, flavivirus; D017361:Viral Nonstructural Proteins