North American West Nile virus genotype isolates demonstrate differential replicative capacities in response to temperature

Christy C. Andrade, Payal D. Maharaj, William Reisen, Aaron Brault

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

The presence of West Nile virus (WNV) was first documented in California, USA, during the summer of 2003, and subsequently the virus has become endemic throughout the state. Sequence analysis has demonstrated that the circulating strains are representative of the North American (WN02) genotype that has displaced the East Coast genotype (NY99). A recent study has indicated that enhanced vector competence at elevated temperatures may have played a role in the displacement of the East Coast genotype by WN02. In the current study, four WN02 strains from California, including an initial 2003 isolate (COAV997), were compared to strain NY99 in growth curve assays in mosquito and duck embryonic fibroblast (DEF) cell lines at differing, biologically relevant temperatures to assess the relative temperature sensitivities of these natural isolates. COAV997 was significantly debilitated in viral replication in DEF cells at 44 6C. Full-length sequence comparison of COAV997 against the NY99 reference strain revealed non-synonymous mutations in the envelope glycoprotein (V159A), non-structural protein 1 (NS1) (K110N) and non-structural protein 4A (NS4A) (F92L), as well as two mutations in the 39 UTR: CAT at nt 10 772 and AAG at nt 10 851. These non-synonymous mutations were introduced into the NY99 viral backbone by site-directed mutagenesis. A mutant containing the NS1-K110N and NS4A-F92L mutations exhibited a debilitated growth phenotype in DEF cells at 44 6C, similar to that of COAV997. One explanation for the subsistence of this genotype is that COAV997 was obtained from an area of California where avian host species might not present elevated temperatures. These data indicate that the NS1 and NS4A mutations identified in some WN02 isolates could reduce thermal stability and impede replication of virus at temperatures observed in febrile avian hosts.

Original languageEnglish (US)
Pages (from-to)2523-2533
Number of pages11
JournalJournal of General Virology
Volume92
Issue number11
DOIs
StatePublished - Nov 1 2011

Fingerprint

West Nile virus
Genotype
Temperature
Ducks
Mutation
Proteins
Fibroblasts
Untranslated Regions
Virus Replication
Growth
Site-Directed Mutagenesis
Culicidae
Mental Competency
Sequence Analysis
Glycoproteins
Fever
Hot Temperature
Viruses
Phenotype
Cell Line

ASJC Scopus subject areas

  • Virology

Cite this

North American West Nile virus genotype isolates demonstrate differential replicative capacities in response to temperature. / Andrade, Christy C.; Maharaj, Payal D.; Reisen, William; Brault, Aaron.

In: Journal of General Virology, Vol. 92, No. 11, 01.11.2011, p. 2523-2533.

Research output: Contribution to journalArticle

@article{0be3165677314e99af9df1460467df69,
title = "North American West Nile virus genotype isolates demonstrate differential replicative capacities in response to temperature",
abstract = "The presence of West Nile virus (WNV) was first documented in California, USA, during the summer of 2003, and subsequently the virus has become endemic throughout the state. Sequence analysis has demonstrated that the circulating strains are representative of the North American (WN02) genotype that has displaced the East Coast genotype (NY99). A recent study has indicated that enhanced vector competence at elevated temperatures may have played a role in the displacement of the East Coast genotype by WN02. In the current study, four WN02 strains from California, including an initial 2003 isolate (COAV997), were compared to strain NY99 in growth curve assays in mosquito and duck embryonic fibroblast (DEF) cell lines at differing, biologically relevant temperatures to assess the relative temperature sensitivities of these natural isolates. COAV997 was significantly debilitated in viral replication in DEF cells at 44 6C. Full-length sequence comparison of COAV997 against the NY99 reference strain revealed non-synonymous mutations in the envelope glycoprotein (V159A), non-structural protein 1 (NS1) (K110N) and non-structural protein 4A (NS4A) (F92L), as well as two mutations in the 39 UTR: CAT at nt 10 772 and AAG at nt 10 851. These non-synonymous mutations were introduced into the NY99 viral backbone by site-directed mutagenesis. A mutant containing the NS1-K110N and NS4A-F92L mutations exhibited a debilitated growth phenotype in DEF cells at 44 6C, similar to that of COAV997. One explanation for the subsistence of this genotype is that COAV997 was obtained from an area of California where avian host species might not present elevated temperatures. These data indicate that the NS1 and NS4A mutations identified in some WN02 isolates could reduce thermal stability and impede replication of virus at temperatures observed in febrile avian hosts.",
author = "Andrade, {Christy C.} and Maharaj, {Payal D.} and William Reisen and Aaron Brault",
year = "2011",
month = "11",
day = "1",
doi = "10.1099/vir.0.032318-0",
language = "English (US)",
volume = "92",
pages = "2523--2533",
journal = "Journal of General Virology",
issn = "0022-1317",
publisher = "Society for General Microbiology",
number = "11",

}

TY - JOUR

T1 - North American West Nile virus genotype isolates demonstrate differential replicative capacities in response to temperature

AU - Andrade, Christy C.

AU - Maharaj, Payal D.

AU - Reisen, William

AU - Brault, Aaron

PY - 2011/11/1

Y1 - 2011/11/1

N2 - The presence of West Nile virus (WNV) was first documented in California, USA, during the summer of 2003, and subsequently the virus has become endemic throughout the state. Sequence analysis has demonstrated that the circulating strains are representative of the North American (WN02) genotype that has displaced the East Coast genotype (NY99). A recent study has indicated that enhanced vector competence at elevated temperatures may have played a role in the displacement of the East Coast genotype by WN02. In the current study, four WN02 strains from California, including an initial 2003 isolate (COAV997), were compared to strain NY99 in growth curve assays in mosquito and duck embryonic fibroblast (DEF) cell lines at differing, biologically relevant temperatures to assess the relative temperature sensitivities of these natural isolates. COAV997 was significantly debilitated in viral replication in DEF cells at 44 6C. Full-length sequence comparison of COAV997 against the NY99 reference strain revealed non-synonymous mutations in the envelope glycoprotein (V159A), non-structural protein 1 (NS1) (K110N) and non-structural protein 4A (NS4A) (F92L), as well as two mutations in the 39 UTR: CAT at nt 10 772 and AAG at nt 10 851. These non-synonymous mutations were introduced into the NY99 viral backbone by site-directed mutagenesis. A mutant containing the NS1-K110N and NS4A-F92L mutations exhibited a debilitated growth phenotype in DEF cells at 44 6C, similar to that of COAV997. One explanation for the subsistence of this genotype is that COAV997 was obtained from an area of California where avian host species might not present elevated temperatures. These data indicate that the NS1 and NS4A mutations identified in some WN02 isolates could reduce thermal stability and impede replication of virus at temperatures observed in febrile avian hosts.

AB - The presence of West Nile virus (WNV) was first documented in California, USA, during the summer of 2003, and subsequently the virus has become endemic throughout the state. Sequence analysis has demonstrated that the circulating strains are representative of the North American (WN02) genotype that has displaced the East Coast genotype (NY99). A recent study has indicated that enhanced vector competence at elevated temperatures may have played a role in the displacement of the East Coast genotype by WN02. In the current study, four WN02 strains from California, including an initial 2003 isolate (COAV997), were compared to strain NY99 in growth curve assays in mosquito and duck embryonic fibroblast (DEF) cell lines at differing, biologically relevant temperatures to assess the relative temperature sensitivities of these natural isolates. COAV997 was significantly debilitated in viral replication in DEF cells at 44 6C. Full-length sequence comparison of COAV997 against the NY99 reference strain revealed non-synonymous mutations in the envelope glycoprotein (V159A), non-structural protein 1 (NS1) (K110N) and non-structural protein 4A (NS4A) (F92L), as well as two mutations in the 39 UTR: CAT at nt 10 772 and AAG at nt 10 851. These non-synonymous mutations were introduced into the NY99 viral backbone by site-directed mutagenesis. A mutant containing the NS1-K110N and NS4A-F92L mutations exhibited a debilitated growth phenotype in DEF cells at 44 6C, similar to that of COAV997. One explanation for the subsistence of this genotype is that COAV997 was obtained from an area of California where avian host species might not present elevated temperatures. These data indicate that the NS1 and NS4A mutations identified in some WN02 isolates could reduce thermal stability and impede replication of virus at temperatures observed in febrile avian hosts.

UR - http://www.scopus.com/inward/record.url?scp=80053939694&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=80053939694&partnerID=8YFLogxK

U2 - 10.1099/vir.0.032318-0

DO - 10.1099/vir.0.032318-0

M3 - Article

C2 - 21775581

AN - SCOPUS:80053939694

VL - 92

SP - 2523

EP - 2533

JO - Journal of General Virology

JF - Journal of General Virology

SN - 0022-1317

IS - 11

ER -