P0DOF7 · M1_I72A8
- ProteinMatrix protein 1
- GeneM
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids252 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score4/5
Function
function
Plays critical roles in virus replication, from virus entry and uncoating to assembly and budding of the virus particle. M1 binding to ribonucleocapsids (RNPs) in nucleus seems to inhibit viral transcription. Interaction of viral NEP with M1-RNP is thought to promote nuclear export of the complex, which is targeted to the virion assembly site at the apical plasma membrane in polarized epithelial cells. Interactions with NA and HA may bring M1, a non-raft-associated protein, into lipid rafts. Forms a continuous shell on the inner side of the lipid bilayer in virion, where it binds the RNP. During virus entry into cell, the M2 ion channel acidifies the internal virion core, inducing M1 dissociation from the RNP. M1-free RNPs are transported to the nucleus, where viral transcription and replication can take place.
Determines the virion's shape: spherical or filamentous. Clinical isolates of influenza are characterized by the presence of significant proportion of filamentous virions, whereas after multiple passage on eggs or cell culture, virions have only spherical morphology. Filamentous virions are thought to be important to infect neighboring cells, and spherical virions more suited to spread through aerosol between hosts organisms.
Miscellaneous
Most abundant protein in virion. When expressed alone can form virus-like particles in transfected cells.
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | host cell nucleus | |
Cellular Component | membrane | |
Cellular Component | virion membrane | |
Molecular Function | RNA binding | |
Molecular Function | structural constituent of virion | |
Biological Process | viral budding from plasma membrane |
Keywords
- Molecular function
Names & Taxonomy
Protein names
- Recommended nameMatrix protein 1
- Short namesM1
Gene names
Organism names
- Taxonomic lineageViruses > Riboviria > Orthornavirae > Negarnaviricota > Polyploviricotina > Insthoviricetes > Articulavirales > Orthomyxoviridae > Alphainfluenzavirus > Alphainfluenzavirus influenzae > Influenza A virus
- Virus hosts
Accessions
- Primary accessionP0DOF7
- Secondary accessions
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Virion membrane ; Peripheral membrane protein
Keywords
- Cellular component
Phenotypes & Variants
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 41 | No effect on filamentous virion particles morphology. | ||||
Sequence: A → V | ||||||
Mutagenesis | 95 | Complete loss of filamentous virion particles morphology. | ||||
Sequence: R → K | ||||||
Mutagenesis | 167 | No effect on filamentous virion particles morphology. | ||||
Sequence: A → T | ||||||
Mutagenesis | 168 | No effect on filamentous virion particles morphology. | ||||
Sequence: T → A | ||||||
Mutagenesis | 204 | Complete loss of filamentous virion particles morphology. | ||||
Sequence: E → D | ||||||
Mutagenesis | 205 | No effect on filamentous virion particles morphology. | ||||
Sequence: V → I | ||||||
Mutagenesis | 218 | No effect on filamentous virion particles morphology. | ||||
Sequence: A → T |
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000078866 | 1-252 | Matrix protein 1 | |||
Sequence: MSLLTEVETYVLSIVPSGPLKAEIAQRLEDVFAGKNTDLEALMEWLKTRPILSPLTKGILGFVFTLTVPSERGLQRRRFVQNALNGNGDPNNMDRAVKLYRKLKREITFHGAKEIALSYSAGALASCMGLIYNRMGAVTTEVAFGLVCATCEQIADSQHRSHRQMVATTNPLIRHENRMVLASTTAKAMEQMAGSSEQAAEAMEVASQARQMVQAMRAIGTHPSSSAGLKDDLLENLQAYQKRMGVQMQRFK |
Interaction
Subunit
Homodimer and homomultimer. Interacts with NEP. Binds ribonucleocapsid by both interacting with genomic RNA and NP protein. May interact with HA and NA. Cannot bind NP without genomic RNA.
Family & Domains
Features
Showing features for region, motif.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 1-164 | Membrane-binding | ||||
Sequence: MSLLTEVETYVLSIVPSGPLKAEIAQRLEDVFAGKNTDLEALMEWLKTRPILSPLTKGILGFVFTLTVPSERGLQRRRFVQNALNGNGDPNNMDRAVKLYRKLKREITFHGAKEIALSYSAGALASCMGLIYNRMGAVTTEVAFGLVCATCEQIADSQHRSHRQ | ||||||
Motif | 101-105 | Nuclear localization signal | ||||
Sequence: RKLKR | ||||||
Region | 165-252 | RNP-binding | ||||
Sequence: MVATTNPLIRHENRMVLASTTAKAMEQMAGSSEQAAEAMEVASQARQMVQAMRAIGTHPSSSAGLKDDLLENLQAYQKRMGVQMQRFK |
Sequence similarities
Belongs to the influenza viruses Matrix protein M1 family.
Family and domain databases
Sequence & Isoform
- Sequence statusComplete
This entry describes 2 isoforms produced by Alternative splicing. Only the first 9 residues are shared by the 2 isoforms.
P0DOF7-1
This isoform has been chosen as the canonical sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.
- NameM1
- Length252
- Mass (Da)27,804
- Last updated2017-05-10 v1
- Checksum92522D3E87D4C3C6
P0DOF8-1
The sequence of this isoform can be found in the external entry linked below. Isoforms of the same protein are often annotated in two different entries if their sequences differ significantly.
View isoform- NameM2
Keywords
- Coding sequence diversity