Matrix 1 protein (M1) (M1)

The Matrix 1 protein (M1) is the most abundant structural protein in the influenza A virus, including the highly pathogenic H5N1 avian strain. It forms a protein scaffold beneath the viral lipid envelope, providing structural integrity and determining the morphology of the virion. M1 plays a critical role throughout the viral life cycle, facilitating viral uncoating during entry, mediating the nuclear export of viral ribonucleoproteins (vRNPs) through interactions with the nuclear export protein (NEP), and orchestrating viral assembly and budding at the plasma membrane [2, 3, 7]. Beyond its structural roles, M1 has been implicated in regulating viral polymerase activity and inducing host cell apoptosis via Toll-like receptor 4 (TLR4) signaling, which contributes to the severe lung pathology seen in H5N1 infections [8, 17]. While no M1-specific inhibitors are currently approved for clinical use, the protein is a major target for universal vaccine development due to its high conservation across influenza subtypes [12, 14]. Experimental therapeutic strategies include monoclonal antibodies, antisense oligonucleotides, and peptides designed to disrupt its essential protein-protein interactions or its role in viral morphogenesis [11, 12, 18].

Other names

Matrix protein 1M1 proteinInfluenza A virus M1Matrix protein M1

Inhibition of viral uncoating, nuclear export, and assembly/budding; neutralization of extracellular M1-mediated TLR4 activation.