Glycosylation of the dengue 2 virus E protein at N67 is critical for virus growth in vitro but not for growth in intrathoracically inoculated Aedes aegypti mosquitoes.
To determine the importance of dengue 2 virus (DEN2V) envelope (E) protein glycosylation, virus mutants in one or both of the N-linked glycosylation motifs were prepared. We found that while the E2 mutant virus (N153Q) replicated in mammalian and mosquito cells, the E1 (N67Q) and E1/2 (N67Q and N153Q) mutant viruses were unable to grow in mammalian cells. Infection of C6/36 mosquito cells with either the E1 or E1/2 mutants resulted in the introduction of a compensatory mutation, K64N, restoring glycosylation in the area. All mutants replicated similarly in inoculated Aedes aegypti mosquitoes, with no change in their mutations. These results suggest that N-linked glycosylation of the E protein is not necessary for DEN2V replication in mosquitoes, however N-linked glycosylation at amino acid N67 (or nearby N64) is critical for the survival of the virus in either mammalian or insect cell culture.
Bryant
Juliet E
JE
Arboviral Diseases Branch, Division of Vector-Borne Infectious Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, U.S. Department of Health and Human Services, Fort Collins, CO 80522, USA.
Calvert
Amanda E
AE
Mesesan
Kyeen
K
Crabtree
Mary B
MB
Volpe
Katharine E
KE
Silengo
Shawn
S
Kinney
Richard M
RM
Huang
Claire Y-H
CY
Miller
Barry R
BR
Roehrig
John T
JT
D000330:Aedes / Q000821:virology*; D019943:Amino Acid Substitution / Q000235:genetics; D000818:Animals; D002460:Cell Line; D003716:Dengue Virus / Q000235:genetics / Q000254:growth & development*; D006031:Glycosylation; D006801:Humans; D016297:Mutagenesis, Site-Directed; D014759:Viral Envelope Proteins / Q000235:genetics / Q000378:metabolism*
C051821:E-glycoprotein, Dengue virus type 2; D014759:Viral Envelope Proteins