Contents

M1 protein

Flu_M1
influenza virus m1 protein
Identifiers
Symbol	Flu_M1
Pfam	PF00598
InterPro	IPR001561
SCOP2	1aa7 / SCOPe / SUPFAM
OPM superfamily	42
OPM protein	1aa7
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

The M1 protein is a matrix protein of the influenza virus. It forms a coat inside the viral envelope. This is a bifunctional membrane/RNA-binding protein that mediates the encapsidationofnucleoprotein cores into the membrane envelope. It is therefore required that M1 binds both membrane and RNA simultaneously.^[1]

The M1 protein binds to the viral RNA. The binding is not specific to any RNA sequence, and is performed via a peptide sequence rich in basic amino acids.^{[citation needed]}

It also has multiple regulatory functions, performed by interaction with the components of the host cell. The mechanisms regulated include a role in the export of the viral ribonucleoproteins from the host cell nucleus, inhibition of viral transcription, and a role in the virus assembly and budding. The protein was found to undergo phosphorylation in the host cell.^{[citation needed]}

The M1 protein forms a layer under the patches of host cell membrane that are rich with the viral hemagglutinin, neuraminidase and M2 transmembrane proteins, and facilitates budding of the mature viruses.^{[citation needed]}

M1 consists of two domains connected by a linker sequence. The N-terminal domain has a multi-helical structure that can be divided into two subdomains.^[2] The C-terminal domain also contains alpha-helical structure.

• H5N1 genetic structure