Severe acute respiratory syndrome coronavirus 2 membrane protein (M protein)

The SARS-CoV-2 membrane protein (M protein) is the most abundant structural protein in the viral envelope. It contains three transmembrane domains and forms homodimers, organizing the assembly of virions via protein-protein interactions with itself and other structural proteins (spike [S], envelope [E], and nucleocapsid [N]). The M protein recruits these proteins to the endoplasmic reticulum-Golgi intermediate compartment (ERGIC), driving the formation of virus-like particles and enabling budding of new virions. Structural studies show the M protein has a mushroom-shaped dimer conformation, with a conserved hinge region allowing for flexibility. It shares homology with certain prokaryotic transport proteins and the SARS-CoV-2 ORF3a viroporin. The M protein’s interaction with N protein and RNA is crucial for viral assembly and has recently been proposed as a novel therapeutic target due to its central role in the virus life cycle. M protein is recognized by antibodies in infected patients, making it a potential biomarker for infection. This entry describes one of four core structural proteins of SARS-CoV-2; it is not a human receptor but rather an essential viral protein for SARS-CoV-2 infection and pathogenicity. There is no evidence of direct clinical drugs currently targeting the M protein, but its central role in viral assembly makes it an important subject in drug development.

Other names

SARS-CoV-2 M proteinCoronavirus M proteinMembrane protein MMatrix proteinE1 protein

Drugs or interventions would inhibit virus assembly or budding by interfering with M protein interactions or structure