Recombinant Human metapneumovirus Matrix protein(M)

Has a crucial role in virus assembly and budding. The matrix interacts with the RNP complex and this association serves two functions: facilitate virion assembly and inhibit the viral transcriptase activity. Early in infection, M is localized to the nucleus and may inhibit host cell transcription. Later on, M can associate with lipid rafts supposely by interacting with the cytoskeleton and with the cytoplasmic tail of glycoprotein G. The binding of M to host membrane is stabilized by the surface expression of the viral glycoproteins. These interactions may allow virus formation by mediating association of the nucleocapsid with the nascent envelope (By similarity).