title: West Nile virus discriminates between DC-SIGN and DC-SIGNR for cellular attachment and infection.
abstract: The C-type lectins DC-SIGN and DC-SIGNR bind mannose-rich glycans with high affinity. In vitro, cells expressing these attachment factors efficiently capture, and are infected by, a diverse array of appropriately glycosylated pathogens, including dengue virus. In this study, we investigated whether these lectins could enhance cellular infection by West Nile virus (WNV), a mosquito-borne flavivirus related to dengue virus. We discovered that DC-SIGNR promoted WNV infection much more efficiently than did DC-SIGN, particularly when the virus was grown in human cell types. The presence of a single N-linked glycosylation site on either the prM or E glycoprotein of WNV was sufficient to allow DC-SIGNR-mediated infection, demonstrating that uncleaved prM protein present on a flavivirus virion can influence viral tropism under certain circumstances. Preferential utilization of DC-SIGNR was a specific property conferred by the WNV envelope glycoproteins. Chimeras between DC-SIGN and DC-SIGNR demonstrated that the ability of DC-SIGNR to promote WNV infection maps to its carbohydrate recognition domain. WNV virions and subviral particles bound to DC-SIGNR with much greater affinity than DC-SIGN. We believe this is the first report of a pathogen interacting more efficiently with DC-SIGNR than with DC-SIGN. Our results should lead to the discovery of new mechanisms by which these well-studied lectins discriminate among ligands.
authors.affiliation: Department of Microbiology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
authors.forename: Carl W
authors.initials: CW
authors.lastname: Davis
authors.forename: Hai-Yen
authors.initials: HY
authors.lastname: Nguyen
authors.forename: Sheri L
authors.initials: SL
authors.lastname: Hanna
authors.forename: Melissa D
authors.initials: MD
authors.lastname: Sánchez
authors.forename: Robert W
authors.initials: RW
authors.lastname: Doms
authors.forename: Theodore C
authors.initials: TC
authors.lastname: Pierson
mesh_terms: D000818:Animals; D001665:Binding Sites; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000502:physiology*; D002460:Cell Line; D006224:Cricetinae; D006031:Glycosylation; D006367:HeLa Cells; D006801:Humans; D037181:Lectins, C-Type / Q000235:genetics / Q000502:physiology*; D008024:Ligands; D009154:Mutation; D011956:Receptors, Cell Surface / Q000235:genetics / Q000502:physiology*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D014774:Virulence; D014902:West Nile virus / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin
chemical_list: D015815:Cell Adhesion Molecules; D037181:Lectins, C-Type; D008024:Ligands; D011956:Receptors, Cell Surface; D011994:Recombinant Proteins; D014759:Viral Envelope Proteins; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin; C433029:CLEC4M protein, human; C074932:prM protein, Flavivirus