Influenza internal proteins

Influenza internal proteins are a group of highly conserved viral proteins located within the viral envelope, including the nucleoprotein (NP), matrix protein (M1), and the heterotrimeric RNA polymerase complex (PA, PB1, and PB2) (Bouvier & Palese, 2008). Unlike the surface glycoproteins hemagglutinin and neuraminidase, which undergo frequent antigenic drift, these internal proteins remain relatively stable across different influenza strains and subtypes (Sridhar et al., 2013). They perform critical roles in the viral life cycle, such as RNA replication, transcription, viral assembly, and evasion of the host's innate immune system (UniProt Consortium, 2023). Because of their high conservation, they are primary targets for the development of universal influenza vaccines aimed at inducing cross-reactive T-cell responses that can recognize multiple virus subtypes (Sridhar et al., 2013). Additionally, several small-molecule antivirals have been developed to inhibit the enzymatic activities of the polymerase complex, such as Baloxavir marboxil, which targets the PA subunit, providing therapeutic options against both seasonal and pandemic influenza (Hayden & Shindo, 2019).

Other names

Conserved influenza proteinsInternal viral antigensInfluenza core proteinsInfluenza virus internal proteinsInternal genes

Inhibition of the viral RNA-dependent RNA polymerase complex (specifically the PA endonuclease and PB2 cap-binding subunits), blockade of the M2 ion channel to prevent viral uncoating, and induction of heterosubtypic T-cell immunity against conserved epitopes.