Yellow fever virus nonstructural protein 1 (NS1)

Yellow fever virus nonstructural protein 1 (NS1) is a glycosylated viral protein of approximately 352 amino acids, highly conserved among flaviviruses, and essential for viral genome replication and pathogenesis. It exists as a dimer in the endoplasmic reticulum and is involved in viral RNA replication and virion maturation; it is also secreted as higher-order oligomers—such as tetramers or hexamers—into the extracellular environment, where it acts as an immune evasion factor and virulence determinant[1][2][3][4]. Secreted NS1 can interact with host complement proteins, disrupting the innate immune response, and is used as a diagnostic marker for early detection of yellow fever virus infection[2][3][4]. NS1 lacks a canonical transmembrane domain, but can be expressed on the cell surface, and its various glycosylation and disulfide-bonded forms are critical for its stability, function, and pathogenicity[1][2][4]. The protein is an attractive target for both diagnostics and therapeutic antibody development, but currently, there are no approved drugs specifically targeting YFV NS1[2][3].

Other names

NS1Nonstructural protein 1YFV NS1Flavivirus NS1

Inhibition of viral replication (for drugs/antibodies targeting NS1) Immune neutralization (antibody-mediated)