Enveloped viruses rely on matrix proteins for structural integrity and lifecycle progression. Matrix protein 1 (M1) is the most abundant structural protein of influenza A virus (IAV), playing a multifaceted role in viral uncoating, polymerase activity, vRNA transcription and replication, and assembly and budding. The M1 protein not only interacts with host cells but also regulates viral morphogenesis, thereby influencing viral transmissibility and pathogenicity. These properties make it a highly promising antiviral target. This review elucidates the intricate structure and function of M1, highlighting its regulatory influence on IAV replication and adaptation, and providing critical insights into viral replication dynamics and epidemiological shifts.

Beyond engaging host factors, the M1 protein orchestrates virion morphogenesis—thereby shaping viral transmissibility and pathogenicity—making it a highly attractive antiviral target.