M2

The Matrix protein M2 forms a protons channel. When the environmental pH is lower than a threshold, the M2 channel is activated and selectively transports protons accross the membrane from the extracellular side to the cytoplasmic side. It is crucial for the uncoating process. When the virion is internalized into the endosome the channel can acidify the virion interior, promoting the dissociation of the viral matrix protein (M1) from the ribonucleoprotein (RNP) thus allowing the transport of the RNP from the virion into the cell's nucleus. For some influenza virus subtypes, the M2 channel can elevate the intravesicular pH of the trans Golgi network, preventing the viral protein haemagglutinin, which is transported to the cell surface through the trans Golgi network, from incorrect maturation in an otherwise low pH environment.

Influenza A Virus M2 Protein; Influenza A; Influenza Aantigen; Isavirus; Thogotovirus; Orthomyxoviridae; Matrix protein M2; matrix (M2/22K); M2/22K; Matrix; Influenza A virus matrix protein M2; M; M2; Membrane ion channel M2; Membrane protein M2; Proton channel protein M2; Influenza A Virus M2 Protein; M2 Protein;