Influenza A virus polymerase basic protein 1 (PB1)

Influenza A virus polymerase basic protein 1 (PB1) is the catalytic core of the heterotrimeric RNA-dependent RNA polymerase (RdRp) complex, which is essential for the replication and transcription of the viral genome (UniProt: P03433). Unlike the surface glycoproteins hemagglutinin and neuraminidase, which undergo frequent antigenic drift, PB1 is highly conserved across various influenza A subtypes, including H1N1, H3N2, and H5N1 (Assarsson et al., J Virol, 2008). This conservation makes PB1 a primary target for the development of universal influenza vaccines that utilize T-cell epitopes to provide broad-spectrum immunity. T-cells recognizing these conserved epitopes can identify and destroy infected cells across different viral strains, potentially mitigating the impact of seasonal shifts and future pandemics (Gras et al., J Immunol, 2010). In addition to vaccine development, PB1 is a target for small-molecule antivirals such as Favipiravir, which acts as a nucleotide analogue that is incorporated into the viral RNA, leading to the termination of RNA synthesis or lethal mutagenesis (Furuta et al., Antiviral Res, 2013). Therapeutic strategies focusing on PB1 conserved T-cell epitopes aim to provide long-lasting, cross-protective cellular immunity that complements the strain-specific humoral immunity provided by traditional vaccines. However, the effectiveness of such T-cell-based therapies is often dependent on the host's Human Leukocyte Antigen (HLA) profile, which determines the presentation of these epitopes to the immune system (Hillaire et al., J Virol, 2013).

Other names

RNA-directed RNA polymerase catalytic subunitPolymerase basic protein 1PB1 subunitInfluenza A virus PB1PB1 protein

Inhibition of viral RNA-dependent RNA polymerase activity through chain termination or lethal mutagenesis, or induction of cross-reactive CD8+ and CD4+ T-cell mediated immunity against conserved internal viral peptides to clear infected cells (Furuta et al., Antiviral Res, 2013; Atsmon et al., Sci Rep, 2012).