TY - JOUR
T1 - A mouse cell-adapted NS4B mutation attenuates West Nile virus RNA synthesis
AU - Puig-Basagoiti, Francesc
AU - Tilgner, Mark
AU - Bennett, Corey J.
AU - Zhou, Yangsheng
AU - Muñoz-Jordán, Jorge L.
AU - García-Sastre, Adolfo
AU - Bernard, Kristen A.
AU - Shi, Pei Yong
N1 - Funding Information:
We are grateful to Margo Brinton for providing C3H/He and BHK-21 cells, and to Brett Forshey, Chrystal Butler, and Barbara Stewart for technical assistance. We also thank the Molecular Genetics Core and the Cell Culture Facility at the Wadsworth Center for DNA sequencing and for maintenance of BHK-21 and Vero cells, respectively. The work was supported in part by funds from the NIH/NIAID under contract N01-AI25490 and grants AI061193 and AI065562. Work in AG-S laboratory was partially supported by the Northeast Biodefense Center under NIH/NIAD grant U54 AI57518. The BSL-3 animal facility at the Wadsworth Center was used, which is funded in part by the Northeast Biodefense Center's animal core (NIH/NIAID U54AI57158).
PY - 2007/4/25
Y1 - 2007/4/25
N2 - An adaptive mutation (E249G) within West Nile virus (WNV) NS4B gene was consistently recovered from replicon RNAs in C3H/He mouse cells. The E249G is located at the C-terminal tail of NS4B predicted to be on the cytoplasmic side of the endoplasmic reticulum membrane. The E249G substitution reduced replicon RNA synthesis. Compared with the wild-type NS4B, the E249G mutant protein exhibited a similar efficiency in evasion of interferon-β response. Recombinant E249G virus exhibited smaller plaques, slower growth kinetics, and lower RNA synthesis than the wild-type virus in a host-dependent manner, with the greatest difference in rodent cells (C3H/He and BHK-21) and the least difference in mosquito cells (C3/36). Selection of revertants of E249G virus identified a second site mutation at residue 246, which could compensate for the low replication phenotype in cell culture. These results demonstrate that distinct residues within the C-terminal tail of flavivirus NS4B are critical for viral replication.
AB - An adaptive mutation (E249G) within West Nile virus (WNV) NS4B gene was consistently recovered from replicon RNAs in C3H/He mouse cells. The E249G is located at the C-terminal tail of NS4B predicted to be on the cytoplasmic side of the endoplasmic reticulum membrane. The E249G substitution reduced replicon RNA synthesis. Compared with the wild-type NS4B, the E249G mutant protein exhibited a similar efficiency in evasion of interferon-β response. Recombinant E249G virus exhibited smaller plaques, slower growth kinetics, and lower RNA synthesis than the wild-type virus in a host-dependent manner, with the greatest difference in rodent cells (C3H/He and BHK-21) and the least difference in mosquito cells (C3/36). Selection of revertants of E249G virus identified a second site mutation at residue 246, which could compensate for the low replication phenotype in cell culture. These results demonstrate that distinct residues within the C-terminal tail of flavivirus NS4B are critical for viral replication.
KW - Flavivirus replication
KW - NS4B
KW - West Nile virus
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U2 - 10.1016/j.virol.2006.11.012
DO - 10.1016/j.virol.2006.11.012
M3 - Article
C2 - 17178141
AN - SCOPUS:34047271094
SN - 0042-6822
VL - 361
SP - 229
EP - 241
JO - Virology
JF - Virology
IS - 1
ER -