The M protein is characterized by three TM domains[64] with C-terminal inside (long) and N-terminal (short) outside.[63] The details of the protein structure is available in UniProt.[65] Through multiple protein–protein interactions, the M protein plays a crucial role in viral intracellular homeostasis.[60] Interaction between M–M, M–S, and M–N proteins takes a special part in viral assembly.[60] The M–S interactions are necessary for the interaction of spike protein in the ERGIC complex, also known as the Golgi complex, which is later incorporated into new viral progenies.[60] The M–N interactions are crucial for the stabilization of the RNP complex (nucleocapsid–RNA complex), which forms the viral core.[60] The M protein and the N protein are the major viral envelope proteins, defining viral shape, but it also takes part in the formation and release of virus-like particles.[60]