Table 1.

Influenza A proteins

Protein	Function
HA	Receptor binding and release of viral genome. Most important antigenic protein. Trimeric structure.
NA	Second most important antigenic determinant. Tetrameric enzymatic protein and target for antiviral treatment.
M2	Tetrameric H+ ion channel and target for antiviral treatment
PB1, PB2, PA	Viral polymerase complex
NP	Nucleoprotein
M1	Structural matrix protein
NS1, NS2, PB1-F2	Regulatory proteins and RNA transport