NS4B protein (Dengue virus) (NS4B)

The NS4B protein of Dengue virus is a 27-kDa integral membrane protein with approximately 248 amino acids, featuring multiple transmembrane domains and localization to endoplasmic reticulum (ER)-derived membranes where it forms part of the viral replication complex. It plays essential roles in viral replication by interacting with other nonstructural proteins such as NS4A (via specific transmembrane regions), NS3 (regulating helicase activity), NS1, and NS2B, as well as forming homodimers and facilitating ER vesicle formation and membrane rearrangement. NS4B also engages host factors like vimentin, PERK, EMC, CypA, MAGT1, and VCP to support replication complex anchoring and protein folding. In disease, NS4B contributes to Dengue virus pathogenesis by evading innate immunity, including inhibition of type I interferon signaling, TBK1 phosphorylation, and stress granule formation, while promoting virus-induced ER alterations that enable efficient RNA replication. As a therapeutic target, NS4B is attractive for antivirals due to its lack of enzymatic activity (relying on protein interactions) and conservation across DENV serotypes, with studies pursuing inhibitors that disrupt key interactions like NS4A-NS4B or NS4B-NS3, though challenges include its dynamic structure, N-glycosylation, and host pathway crosstalk; no approved drugs exist, but cell-based assays support target-based discovery.

Other names

dengue virus nonstructural protein 4BDENV NS4B

Inhibition of NS4A-NS4B interaction, blocking NS4B dimerization, disruption of NS4B-NS3 interaction to impair helicase activity, interference with NS4B membrane topology or protein folding