Hemagglutinin of influenza A virus binds specifically to cell surface nucleolin and plays a role in virus internalization.

Hemagglutinin of influenza A virus binds specifically to cell surface nucleolin and plays a role in virus internalization.
Virology. 2016 Apr 13;494:78-88
Authors: Chan CM, Chu H, Zhang AJ, Leung LH, Sze KH, Kao RY, Chik KK, To KK, Chan JF, Chen H, Jin DY, Liu L, Yuen KY
Abstract
The hemagglutinin (HA) protein of influenza A virus initiates cell entry by binding to sialic acids on target cells. In the current study, we demonstrated that in addition to sialic acids, influenza A/Puerto Rico/8/34 H1N1 (PR8) virus HA specifically binds to cell surface nucleolin (NCL). The interaction between HA and NCL was initially revealed with virus overlay protein binding assay (VOPBA) and subsequently verified with co-immunoprecipitation. Importantly, inhibiting cell surface NCL with NCL antibody, blocking PR8 viruses with purified NCL protein, or depleting endogenous NCL with siRNA all substantially reduced influenza virus internalization. We further demonstrated that NCL was a conserved cellular factor required for the entry of multiple influenza A viruses, including H1N1, H3N2, H5N1, and H7N9. Overall, our findings identified a novel role of NCL in influenza virus life cycle and established NCL as one of the host cell surface proteins for the entry of influenza A virus.
PMID: 27085069 [PubMed - as supplied by publisher]

Source: Virology - April 12, 2016 Category: Virology Authors: Chan CM, Chu H, Zhang AJ, Leung LH, Sze KH, Kao RY, Chik KK, To KK, Chan JF, Chen H, Jin DY, Liu L, Yuen KY Tags: Virology Source Type: research