Influenza B virus matrix protein 1 (M1)

Influenza B virus matrix protein 1 (M1) is the most abundant structural protein of influenza B virus and forms a layer beneath the viral envelope, acting as a bridge between the lipid envelope and the viral ribonucleoprotein (vRNP) core[12][13][3][11]. M1 is critical for multiple steps in the viral lifecycle, including providing structural stability to the virion, mediating viral assembly and budding, and regulating vRNP nuclear export, uncoating, transcription, and replication[1][11][13]. The M1 protein is a bifunctional protein with both membrane- and RNA-binding capabilities, facilitating genome encapsidation inside the viral particle[3][4][13]. The protein consists of an N-terminal globular domain and a flexible C-terminal domain, and undergoes oligomerization to form an endoskeleton under the viral membrane[2][5][13]. Due to its essential roles and evolutionary conservation, M1 is viewed as a promising antiviral target. Mutations or inhibitors that disrupt its function impact viral morphogenesis, transmissibility, and pathogenicity[1][13]. Segment 7 of the influenza B genome encodes the M1 protein[8][11]. Research efforts are ongoing to understand the structural dynamics of M1 for the development of antivirals and improved diagnostics tailored to influenza B virus.

Other names

Matrix protein 1M1 proteinIBV M1

Disruption of M1 oligomerization or membrane association (hypothetical strategy); Inhibition of M1 function to block viral assembly or budding (research or preclinical concept)[1][13].