Non-structural protein 5A, hepatitis C virus (NS5A)

Non-structural protein 5A of hepatitis C virus (NS5A) is a zinc-binding, proline-rich, hydrophilic phosphoprotein essential for the HCV life cycle[1]. NS5A is processed from a large viral polyprotein and localizes to intracellular membranes via a conserved amphipathic α-helix[3]. It is a key component of the viral replication complex, involved in RNA replication, assembly of infectious viral particles, and interaction with both viral and host proteins[1][2][4]. NS5A coordinates multiple functions through its three domains, particularly domain III, which is critical for particle assembly at lipid droplets via interactions with the viral core protein[2][4]. NS5A also modulates host cell interferon responses, contributing to viral persistence and pathogenesis[1][4]. The protein is the target of several direct-acting antivirals (DAAs), which inhibit its function and disrupt HCV replication, making it a validated therapeutic target in hepatitis C infection. Drug resistance and variability between viral genotypes remain key therapeutic challenges[1].

Other names

NS5AHepatitis C virus NS5AHCV nonstructural protein 5A

Inhibition of NS5A function, which blocks viral RNA replication and the assembly of new infectious virus particles; Disruption of NS5A-core interactions crucial for particle formation