Identification of human host proteins contributing to H5N1 influenza virus propagation by membrane proteomics.

The highly pathogenic avian influenza (HPAI) H5N1 virus is a highly virulent pathogen that causes respiratory diseases and death in humans and other animal species worldwide. Because influenza is an enveloped virus, the entry, assembly, and budding of virus particles are essential steps in the viral life cycle, and the virus relies on the participation of host cellular membrane proteins for all of these steps. Thus, we took a comparative membrane proteomics approach by using 2-DE coupled with MALDI-TOF/TOF MS to profile membrane proteins involved in H5N1 virus infection at 6, 12, and 24 h. Forty-two different proteins were found to vary on A549 cells due to H5N1 virus infection. Of these proteins, 57% were membrane or membrane-associated proteins. To further characterize the roles of novel identified proteins in virus propagation, the siRNA technology were applied and complement component C1q binding protein, annexin 2, prohibitin, peroxiredoxin 1 and heat shock protein 90-beta were successfully demonstrated to be contributed to viral propagation. In conclusion, the present study provides important new insight into understanding the roles of host membrane proteins in viral infection progress, and this insight is of particular importance for the development of novel therapeutic strategies.