M2 proton channel

• UniProt: P35938

M2 is a membrane protein in the viral envelope of members of the genus Influenza virus A. M2 allows the flow of protons into the interior of the virus, after the virus has entered within a lysosome in the target cell. Within the lysosome, there is a low pH, resulting in the virus inside the influx of protons and acidification. This leads to a conformational change of hemagglutinin in the viral envelope and the eversion of a fusion sequence that initiates a fusion of the viral envelope and the membrane of the lysosome. After this merger, the virus inside is released into the cytosol with the RNA-containing virus capsids. The M2 protein is a function of the proton transport, a transport protein, and has the shape of a channel.

The matrix protein M2 is one of three integral membrane proteins of the influenza virus virion. Messenger RNA for the M2 protein is produced after the splicing. The end of the infection cycle when the virus surface proteins are anchored to the cell membrane, the M2 protein in the removal of protons involved in the Golgi vesicles, in which the virus proteins are transported to the cell membrane.

Mutations in the transmembrane region of the M2 protein are responsible for some of the resistance to drugs ( amantadine ).