Flavivirus nonstructural protein NS1: Complementary surprises

Complement Activation NS1 to C4b Binding Protein Modulates Binding of Flavivirus Nonstructural Protein

Antagonism of the complement component C4 by flavivirus nonstructural protein NS1

The complement system plays an essential protective role in the initial defense against many microorganisms. Flavivirus NS1 is a secreted nonstructural glycoprotein that accumulates in blood, is displayed on the surface of infected cells, and has been hypothesized to have immune evasion functions. Herein, we demonstrate that dengue virus (DENV), West Nile virus (WNV), and yellow fever virus (YF...

Genetic interaction of flavivirus nonstructural proteins NS1 and NS4A as a determinant of replicase function.

Nonstructural protein 1 (NS1) of yellow fever virus (YF) is a glycoprotein localized to extracytoplasmic compartments within infected cells. We have previously shown that NS1 can be supplied in trans and is required for viral RNA replication, a process thought to occur in membrane-bound cytoplasmic complexes. Here we report that the NS1 gene from a related virus, dengue virus (DEN), is unable t...

Role of nonstructural protein NS2A in flavivirus assembly.

Flavivirus nonstructural (NS) proteins are involved in RNA replication and modulation of the host antiviral response; however, evidence is mounting that some NS proteins also have essential roles in virus assembly. Kunjin virus (KUN) NS2A is a small, hydrophobic, transmembrane protein that is part of the replication complex and inhibits interferon induction. Previously, we have shown that an is...

Nonstructural protein NS1: giving a new structure to dengue diagnosis.

In a recent article (6), Wang et al. reported an extensive evaluation of NS1 antigen and compared it with real-time PCR, an IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA), and a hemagglutination inhibition assay for diagnosis of dengue virus infection. The authors reported MAC-ELISA positivity for 46 (92%) out of 50 samples positive for dengue virus by real-time PCR (RT-PCR)...