Characterization of a 105-kDa plasma membrane associated glycoprotein that is involved in West Nile virus binding and infection.
This study attempts to isolate and characterize West Nile virus-binding molecules on the plasma membrane of Vero and murine neuroblastoma cells that is responsible for virus entry. Pretreatment of Vero cells with proteases, glycosidases (endoglycosidase H, alpha-mannosidase), and sodium periodate strongly inhibited West Nile virus infection, whereas treatments with phospholipases and heparinases had no effect. The virus overlay protein blot detected a 105-kDa molecule on the plasma membrane extract of Vero and murine neuroblastoma cells that bind to WN virus. Treatment of the 105-kDa molecules with beta-mercaptoethanol resulted in the virus binding to a series of lower molecular weight bands ranging from 30 to 40 kDa. The disruption of disulfide-linked subunits did not affect virus binding. N-linked sugars with mannose residues on the 105-kDa membrane proteins were found to be important in virus binding. Specific antibodies against the 105-kDa glycoprotein were highly effective in blocking virus entry. These results strongly supported the possibility that the 105-kDa protease-sensitive glycoprotein with complex N-linked sugars could be the putative receptor for WN virus.
Chu
J J H
JJ
Department of Microbiology, 5 Science Drive 2, National University of Singapore, Singapore 117597, Singapore.
Ng
M L
ML
D000818:Animals; D002462:Cell Membrane / Q000378:metabolism*; D002522:Chlorocebus aethiops; D006023:Glycoproteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D051379:Mice; D008970:Molecular Weight; D009447:Neuroblastoma / Q000378:metabolism; D011485:Protein Binding; D021381:Protein Transport; D011991:Receptors, Virus / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D014709:Vero Cells; D014902:West Nile virus / Q000378:metabolism*
D006023:Glycoproteins; D011991:Receptors, Virus