Matrix protein 2

Function

Forms a proton-selective ion channel that is necessary for the efficient release of the viral genome during virus entry. After attaching to the cell surface, the virion enters the cell by endocytosis. Acidification of the endosome triggers M2 ion channel activity. The influx of protons into virion interior is believed to disrupt interactions between the viral ribonucleoprotein (RNP), matrix protein 1 (M1), and lipid bilayers, thereby freeing the viral genome from interaction with viral proteins and enabling RNA segments to migrate to the host cell nucleus, where influenza virus RNA transcription and replication occur. Also plays a role in viral proteins secretory pathway. Elevates the intravesicular pH of normally acidic compartments, such as trans-Golgi network, preventing newly formed hemagglutinin from premature switching to the fusion-active conformation.

Classification

Family (Pfam)

PF00599 Flu_M2

InterPro

Flu_M2

Functional cluster

Photosystem II Reaction-Center & Antimicrobial Peptides

Experimental structures · PDB · 1

• 5DLM X-ray 2.20A

A predicted model is available from AlphaFold.

Gene Ontology · 10

• GO:0005576 extracellular region
• GO:0020002 host cell plasma membrane
• GO:0005886 plasma membrane
• GO:0055036 virion membrane
• GO:0005216 monoatomic ion channel activity
• GO:0015078 proton transmembrane transporter activity
• GO:0051259 protein complex oligomerization
• GO:0044694 symbiont genome entry into host cell via pore formation in plasma membrane
• GO:0140321 symbiont-mediated suppression of host autophagy
• GO:0019061 uncoating of virus

Drugs targeting this protein · 1

• AMANTADINE HYDROCHLORIDE inhibitor

Related proteins · sequence + function similarity

• Matrix protein 2 0.98
• Matrix protein 2 0.96
• Matrix protein 2 0.96
• Matrix protein 2 0.95
• Matrix protein 2 0.95
• Matrix protein 2 0.95
• Matrix protein 2 0.94
• Matrix protein 2 0.94
• Matrix protein 2 0.93
• Matrix protein 2 0.93
• Matrix protein 2 0.93
• Matrix protein 2 0.93

Co-cited proteins · studied together in the literature

• Matrix protein 1 3 shared papers
• Hemagglutinin 2 shared papers
• PB2-S1 2 shared papers
• Nucleoprotein 2 shared papers
• Protein PA-X 2 shared papers
• Neuraminidase 2 shared papers
• Nuclear export protein 2 shared papers
• RNA-directed RNA polymerase catalytic subunit 2 shared papers
• Non-structural protein 1 2 shared papers
• Matrix protein 2 2 shared papers
• Polymerase basic protein 2 2 shared papers
• Polymerase acidic protein 2 shared papers

Literature · 7 cited papers

• Influenza type a virus escape mutants emerge in vivo in the presence of antibodies to the ectodomain of matrix protein 2. J. Virol. · 2005
• Assembly and budding of influenza virus. Virus Res. · 2004
• Efficient generation and growth of influenza virus A/PR/8/34 from eight cDNA fragments. Virus Res. · 2004
• Computational studies of proton transport through the M2 channel. FEBS Lett. · 2003
• Proton conduction through the M2 protein of the influenza A virus; a quantitative, mechanistic analysis of experimental data. FEBS Lett. · 2003
• Plasmid-only rescue of influenza A virus vaccine candidates. Philos. Trans. R. Soc. Lond., B, Biol. Sci. · 2001
• Cloning of influenza cDNA into M13: the sequence of the RNA segment encoding the A/PR/8/34 matrix protein. Nucleic Acids Res. · 1980