Dengue virus non-structural protein 4A-2K-4B precursor (NS4A-2K-NS4B)

The Dengue virus NS4A-2K-NS4B precursor is a critical polyprotein intermediate required for the assembly of the viral replication complex and the modulation of host cell environments. It consists of the NS4A protein, a 2-kDa (2K) signal peptide, and the NS4B protein. NS4A is essential for inducing the curvature of the host endoplasmic reticulum (ER) membrane to create protected compartments for viral RNA synthesis (Miller et al., 2007, J. Biol. Chem.). The 2K peptide serves as a signal sequence that directs the translocation of NS4B into the ER membrane; its cleavage is a highly regulated two-step process involving the viral NS2B-NS3 protease and host signal peptidase (Zou et al., 2015, Antiviral Res.). NS4B itself is a multi-pass transmembrane protein that acts as a scaffold for the replication complex and functions as a potent antagonist of the host's innate immune response by blocking interferon-induced STAT1 phosphorylation (Munoz-Jordan et al., 2003, J. Virol.). Due to its indispensable role in the viral life cycle, this precursor and its mature products are major targets for antiviral drug development. Specifically, inhibitors like JNJ-1802 target NS4B to disrupt its interaction with the NS3 helicase, thereby potently inhibiting viral replication across all four Dengue serotypes (Goethals et al., 2023, Nature). Successful inhibition of this target leads to a significant reduction in viral RNA synthesis and prevents the virus from evading the host's primary immune defenses.

Other names

DENV NS4A-2K-NS4BNon-structural protein 4A-2K-4BNS4A-2K-NS4B polyprotein segmentNS4A-2K-NS4B junction

Allosteric inhibition of NS4B and disruption of the NS3-NS4B replication complex interaction