M1_I18A0
ID M1_I18A0 Reviewed; 252 AA.
AC Q8BAC3; O10427;
DT 13-NOV-2007, integrated into UniProtKB/Swiss-Prot.
DT 01-MAR-2003, sequence version 1.
DT 29-SEP-2021, entry version 75.
DE RecName: Full=Matrix protein 1 {ECO:0000255|HAMAP-Rule:MF_04068};
DE Short=M1 {ECO:0000255|HAMAP-Rule:MF_04068};
GN Name=M {ECO:0000255|HAMAP-Rule:MF_04068};
OS Influenza A virus (strain A/Brevig Mission/1/1918 H1N1) (Influenza A virus
OS (strain A/South Carolina/1/1918 H1N1)).
OC Viruses; Riboviria; Orthornavirae; Negarnaviricota; Polyploviricotina;
OC Insthoviricetes; Articulavirales; Orthomyxoviridae; Alphainfluenzavirus.
OX NCBI_TaxID=88776;
OH NCBI_TaxID=8782; Aves.
OH NCBI_TaxID=9606; Homo sapiens (Human).
OH NCBI_TaxID=9823; Sus scrofa (Pig).
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC RNA].
RX PubMed=12368314; DOI=10.1128/jvi.76.21.10717-10723.2002;
RA Reid A.H., Fanning T.G., Janczewski T.A., McCall S., Taubenberger J.K.;
RT "Characterization of the 1918 'Spanish' influenza virus matrix gene
RT segment.";
RL J. Virol. 76:10717-10723(2002).
RN [2]
RP NUCLEOTIDE SEQUENCE [GENOMIC RNA] OF 47-69.
RC STRAIN=A/South Carolina/1/18;
RX PubMed=9065404; DOI=10.1126/science.275.5307.1793;
RA Taubenberger J.K., Reid A.H., Krafft A.E., Bijwaard K.E., Fanning T.G.;
RT "Initial genetic characterization of the 1918 'Spanish' influenza virus.";
RL Science 275:1793-1796(1997).
CC -!- FUNCTION: Plays critical roles in virus replication, from virus entry
CC and uncoating to assembly and budding of the virus particle. M1 binding
CC to ribonucleocapsids (RNPs) in nucleus seems to inhibit viral
CC transcription. Interaction of viral NEP with M1-RNP is thought to
CC promote nuclear export of the complex, which is targeted to the virion
CC assembly site at the apical plasma membrane in polarized epithelial
CC cells. Interactions with NA and HA may bring M1, a non-raft-associated
CC protein, into lipid rafts. Forms a continuous shell on the inner side
CC of the lipid bilayer in virion, where it binds the RNP. During virus
CC entry into cell, the M2 ion channel acidifies the internal virion core,
CC inducing M1 dissociation from the RNP. M1-free RNPs are transported to
CC the nucleus, where viral transcription and replication can take place.
CC {ECO:0000255|HAMAP-Rule:MF_04068}.
CC -!- FUNCTION: Determines the virion's shape: spherical or filamentous.
CC Clinical isolates of influenza are characterized by the presence of
CC significant proportion of filamentous virions, whereas after multiple
CC passage on eggs or cell culture, virions have only spherical
CC morphology. Filamentous virions are thought to be important to infect
CC neighboring cells, and spherical virions more suited to spread through
CC aerosol between hosts organisms. {ECO:0000255|HAMAP-Rule:MF_04068}.
CC -!- SUBUNIT: Homodimer and homomultimer. Interacts with NEP. Binds
CC ribonucleocapsid by both interacting with genomic RNA and NP protein.
CC May interact with HA and NA. Cannot bind NP without genomic RNA.
CC {ECO:0000255|HAMAP-Rule:MF_04068}.
CC -!- SUBCELLULAR LOCATION: Virion membrane {ECO:0000255|HAMAP-
CC Rule:MF_04068}; Peripheral membrane protein {ECO:0000255|HAMAP-
CC Rule:MF_04068}; Cytoplasmic side {ECO:0000255|HAMAP-Rule:MF_04068}.
CC Host nucleus {ECO:0000255|HAMAP-Rule:MF_04068}.
CC -!- ALTERNATIVE PRODUCTS:
CC Event=Alternative splicing; Named isoforms=2;
CC Comment=Only the first 9 residues are shared by the 2 isoforms.;
CC Name=M1;
CC IsoId=Q8BAC3-1; Sequence=Displayed;
CC Name=M2;
CC IsoId=Q8BAC4-1; Sequence=External;
CC -!- MISCELLANEOUS: South Carolina isolate has been sequenced from formalid
CC fixed-lung tissues of a 21-year-old male which died in 1918 at Ft.
CC Jackson, SC. Brevig Mission isolate has been sequenced from lung
CC tissues of an Inuit woman buried in the permafrost in a gravesite near
CC Brevig Mission, Alaska. This sample was recovered by John Hultin,
CC retired pathologist.
CC -!- MISCELLANEOUS: Most abundant protein in virion. When expressed alone
CC can form virus-like particles in transfected cells. {ECO:0000255|HAMAP-
CC Rule:MF_04068}.
CC -!- SIMILARITY: Belongs to the influenza viruses Matrix protein M1 family.
CC {ECO:0000255|HAMAP-Rule:MF_04068}.
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DR EMBL; AY130766; AAN06597.1; -; Genomic_RNA.
DR EMBL; U94896; AAC57066.1; -; Genomic_RNA.
DR SMR; Q8BAC3; -.
DR Proteomes; UP000008430; Genome.
DR GO; GO:0042025; C:host cell nucleus; IEA:UniProtKB-SubCell.
DR GO; GO:0016020; C:membrane; IEA:UniProtKB-KW.
DR GO; GO:0055036; C:virion membrane; IEA:UniProtKB-SubCell.
DR GO; GO:0003723; F:RNA binding; IEA:UniProtKB-UniRule.
DR GO; GO:0039660; F:structural constituent of virion; IEA:UniProtKB-UniRule.
DR GO; GO:0046761; P:viral budding from plasma membrane; IEA:UniProtKB-UniRule.
DR Gene3D; 1.10.10.180; -; 1.
DR Gene3D; 1.20.91.10; -; 1.
DR HAMAP; MF_04068; INFV_M1; 1.
DR InterPro; IPR036039; Flu_matrix_M1.
DR InterPro; IPR013188; Flu_matrix_M1_C.
DR InterPro; IPR001561; Flu_matrix_M1_N.
DR InterPro; IPR015423; Flu_matrix_M1_N_sub1.
DR InterPro; IPR015799; Flu_matrix_M1_N_sub2.
DR InterPro; IPR037533; INFV_M1.
DR Pfam; PF00598; Flu_M1; 1.
DR Pfam; PF08289; Flu_M1_C; 1.
DR SMART; SM00759; Flu_M1_C; 1.
DR SUPFAM; SSF48145; SSF48145; 1.
PE 3: Inferred from homology;
KW Alternative splicing; Host nucleus; Membrane; RNA-binding;
KW Viral matrix protein; Virion.
FT CHAIN 1..252
FT /note="Matrix protein 1"
FT /id="PRO_0000310565"
FT REGION 1..164
FT /note="Membrane-binding"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_04068"
FT REGION 165..252
FT /note="RNP-binding"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_04068"
FT MOTIF 101..105
FT /note="Nuclear localization signal"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_04068"
SQ SEQUENCE 252 AA; 27880 MW; 9FDCEDBCE50FD96F CRC64;
MSLLTEVETY VLSIVPSGPL KAEIAQRLED VFAGKNTDLE ALMEWLKTRP ILSPLTKGIL
GFVFTLTVPS ERGLQRRRFV QNALNGNGDP NNMDRAVKLY RKLKREITFH GAKEVALSYS
AGALASCMGL IYNRMGTVTT EVAFGLVCAT CEQIADSQHR SHRQMVTTTN PLIRHENRMV
LASTTAKAME QMAGSSEQAA EAMEVASQAR QMVQAMRTIG THPSSSAGLK DDLIENLQAY
QKRMGVQMQR FK