ID   M1_I33A0                Reviewed;         252 AA.
AC   P05777;
DT   01-NOV-1988, integrated into UniProtKB/Swiss-Prot.
DT   01-JUL-1989, sequence version 2.
DT   08-NOV-2023, entry version 132.
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/Wilson-Smith/1933 H1N1) (Influenza A virus
OS   (strain A/WS/1933 H1N1)).
OC   Viruses; Riboviria; Orthornavirae; Negarnaviricota; Polyploviricotina;
OC   Insthoviricetes; Articulavirales; Orthomyxoviridae; Alphainfluenzavirus;
OC   Alphainfluenzavirus influenzae; Influenza A virus.
OX   NCBI_TaxID=381518;
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=2701939; DOI=10.1093/nar/17.7.2870;
RA   Zebedee S.L., Lamb R.A.;
RT   "Nucleotide sequences of influenza A virus RNA segment 7: a comparison of
RT   five isolates.";
RL   Nucleic Acids Res. 17:2870-2870(1989).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [GENOMIC RNA].
RX   PubMed=3414185; DOI=10.1016/0168-1702(88)90021-4;
RA   Markushin S., Ghiasi H., Sokolov N., Shilov A., Sinitsin B., Brown D.,
RA   Klimov A., Nayak D.;
RT   "Nucleotide sequence of RNA segment 7 and the predicted amino sequence of
RT   M1 and M2 proteins of FPV/Weybridge (H7N7) and WSN (H1N1) influenza
RT   viruses.";
RL   Virus Res. 10:263-272(1988).
RN   [3]
RP   NUCLEOTIDE SEQUENCE [GENOMIC RNA].
RX   PubMed=3354209; DOI=10.1016/0042-6822(88)90303-0;
RA   Baylor N.W., Zhiping Y.L., Wagner R.R.;
RT   "Transient expression and sequence of the matrix (M1) gene of WSN influenza
RT   A virus in a vaccinia vector.";
RL   Virology 163:618-621(1988).
RN   [4]
RP   MUTAGENESIS OF 101-ARG--ARG-105 AND CYS-148.
RX   PubMed=10438836; DOI=10.1128/jvi.73.9.7467-7473.1999;
RA   Ye Z., Liu T., Offringa D.P., McInnis J., Levandowski R.A.;
RT   "Association of influenza virus matrix protein with ribonucleoproteins.";
RL   J. Virol. 73:7467-7473(1999).
RN   [5]
RP   INTERACTION WITH HA AND NA.
RX   PubMed=10954572; DOI=10.1128/jvi.74.18.8709-8719.2000;
RA   Ali A., Avalos R.T., Ponimaskin E., Nayak D.P.;
RT   "Influenza virus assembly: effect of influenza virus glycoproteins on the
RT   membrane association of M1 protein.";
RL   J. Virol. 74:8709-8719(2000).
RN   [6]
RP   MUTAGENESIS OF CYS-148; CYS-151; ALA-155; HIS-159 AND HIS-162.
RX   PubMed=14573816; DOI=10.1099/vir.0.19389-0;
RA   Hui E.K., Ralston K., Judd A.K., Nayak D.P.;
RT   "Conserved cysteine and histidine residues in the putative zinc finger
RT   motif of the influenza A virus M1 protein are not critical for influenza
RT   virus replication.";
RL   J. Gen. Virol. 84:3105-3113(2003).
RN   [7]
RP   FUNCTION.
RX   PubMed=12604801; DOI=10.1099/vir.0.18803-0;
RA   Bourmakina S.V., Garcia-Sastre A.;
RT   "Reverse genetics studies on the filamentous morphology of influenza A
RT   virus.";
RL   J. Gen. Virol. 84:517-527(2003).
RN   [8]
RP   RETRACTED PAPER.
RX   PubMed=12768027; DOI=10.1128/jvi.77.12.7078-7092.2003;
RA   Hui E.K., Barman S., Yang T.Y., Nayak D.P.;
RT   "Basic residues of the helix six domain of influenza virus M1 involved in
RT   nuclear translocation of M1 can be replaced by PTAP and YPDL late assembly
RT   domain motifs.";
RL   J. Virol. 77:7078-7092(2003).
RN   [9]
RP   RETRACTION NOTICE OF PUBMED:12768027.
RX   PubMed=17005709; DOI=10.1128/jvi.01632-06;
RA   Hui E.K., Barman S., Yang T.Y., Tang D.H., France B., Nayak D.P.;
RT   "Retraction.";
RL   J. Virol. 80:10289-10289(2006).
RN   [10]
RP   MUTAGENESIS OF VAL-41; LYS-95 AND THR-218.
RX   PubMed=15033573; DOI=10.1016/j.virol.2003.12.009;
RA   Elleman C.J., Barclay W.S.;
RT   "The M1 matrix protein controls the filamentous phenotype of influenza A
RT   virus.";
RL   Virology 321:144-153(2004).
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, ECO:0000269|PubMed:12604801}.
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       ECO:0000269|PubMed:12604801}.
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, ECO:0000269|PubMed:10954572}.
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=P05777-1; Sequence=Displayed;
CC       Name=M2;
CC         IsoId=P05780-1; Sequence=External;
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}.
CC   -!- CAUTION: An article reported mutagenesis experiments; however, this
CC       paper was later retracted. {ECO:0000305|PubMed:17005709}.
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DR   EMBL; X08088; CAA30882.1; -; Genomic_RNA.
DR   EMBL; M23920; AAA43252.1; ALT_SEQ; Genomic_RNA.
DR   EMBL; M19374; AAA43352.1; -; Genomic_RNA.
DR   EMBL; L25818; AAA91325.1; -; Genomic_RNA.
DR   PIR; A28608; MFIVWS.
DR   PIR; S07429; S07429.
DR   PDB; 4PUS; X-ray; 2.20 A; A/B=2-165.
DR   PDB; 5V6G; X-ray; 2.00 A; A/B/C/D=2-165.
DR   PDB; 5V7B; X-ray; 2.50 A; A/B=2-165.
DR   PDB; 5V7S; X-ray; 2.50 A; A/B/C=2-165.
DR   PDB; 5V8A; X-ray; 3.00 A; A=2-165.
DR   PDB; 6I3H; X-ray; 1.90 A; A/B=1-158.
DR   PDB; 6QZD; X-ray; 2.66 A; CCC/FFF=17-30.
DR   PDBsum; 4PUS; -.
DR   PDBsum; 5V6G; -.
DR   PDBsum; 5V7B; -.
DR   PDBsum; 5V7S; -.
DR   PDBsum; 5V8A; -.
DR   PDBsum; 6I3H; -.
DR   PDBsum; 6QZD; -.
DR   SMR; P05777; -.
DR   Proteomes; UP000000834; 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; Influenza virus matrix protein M1; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Alternative splicing; Host nucleus; Membrane;
KW   Reference proteome; RNA-binding; Viral matrix protein; Virion.
FT   CHAIN           1..252
FT                   /note="Matrix protein 1"
FT                   /id="PRO_0000078868"
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"
FT   MUTAGEN         41
FT                   /note="V->A: Induces short filamentous virions."
FT                   /evidence="ECO:0000269|PubMed:15033573"
FT   MUTAGEN         95
FT                   /note="K->A,R: No effect."
FT                   /evidence="ECO:0000269|PubMed:15033573"
FT   MUTAGEN         100..103
FT                   /note="YRKL->AAAA,PPPY: Can't be rescued by reverse
FT                   genetic."
FT   MUTAGEN         100..103
FT                   /note="YRKL->PTAP: No effect."
FT   MUTAGEN         101..105
FT                   /note="RKLKR->SNLNS: 50% loss of RNA binding activity."
FT                   /evidence="ECO:0000269|PubMed:10438836"
FT   MUTAGEN         101..102
FT                   /note="RK->PD: No effect."
FT   MUTAGEN         148
FT                   /note="C->A: No effect."
FT                   /evidence="ECO:0000269|PubMed:10438836,
FT                   ECO:0000269|PubMed:14573816"
FT   MUTAGEN         148
FT                   /note="C->S: 31% loss of RNA binding activity."
FT                   /evidence="ECO:0000269|PubMed:10438836,
FT                   ECO:0000269|PubMed:14573816"
FT   MUTAGEN         151
FT                   /note="C->A: No effect."
FT                   /evidence="ECO:0000269|PubMed:14573816"
FT   MUTAGEN         155
FT                   /note="A->G: Complete loss of virus ability to be rescued
FT                   in a reverse genetic system."
FT                   /evidence="ECO:0000269|PubMed:14573816"
FT   MUTAGEN         159
FT                   /note="H->A: No effect."
FT                   /evidence="ECO:0000269|PubMed:14573816"
FT   MUTAGEN         162
FT                   /note="H->A: No effect."
FT                   /evidence="ECO:0000269|PubMed:14573816"
FT   MUTAGEN         218
FT                   /note="T->A: No effect on virion morphology."
FT                   /evidence="ECO:0000269|PubMed:15033573"
FT   CONFLICT        117
FT                   /note="L -> F (in Ref. 3; AAA43352)"
FT   CONFLICT        219
FT                   /note="I -> V (in Ref. 3; AAA43352)"
FT   CONFLICT        231
FT                   /note="D -> S (in Ref. 2; AAA43252)"
FT   HELIX           1..13
FT                   /evidence="ECO:0007829|PDB:6I3H"
FT   HELIX           19..32
FT                   /evidence="ECO:0007829|PDB:6I3H"
FT   HELIX           39..48
FT                   /evidence="ECO:0007829|PDB:6I3H"
FT   STRAND          50..52
FT                   /evidence="ECO:0007829|PDB:5V6G"
FT   HELIX           54..67
FT                   /evidence="ECO:0007829|PDB:6I3H"
FT   HELIX           78..83
FT                   /evidence="ECO:0007829|PDB:6I3H"
FT   HELIX           86..88
FT                   /evidence="ECO:0007829|PDB:5V6G"
FT   HELIX           91..103
FT                   /evidence="ECO:0007829|PDB:6I3H"
FT   HELIX           109..116
FT                   /evidence="ECO:0007829|PDB:6I3H"
FT   HELIX           121..132
FT                   /evidence="ECO:0007829|PDB:6I3H"
FT   HELIX           135..137
FT                   /evidence="ECO:0007829|PDB:6I3H"
FT   HELIX           140..157
FT                   /evidence="ECO:0007829|PDB:6I3H"
SQ   SEQUENCE   252 AA;  27864 MW;  5F300F18D75BBAD3 CRC64;
     MSLLTEVETY VLSIVPSGPL KAEIAQRLED VFAGKNTDLE VLMEWLKTRP ILSPLTKGIL
     GFVFTLTVPS ERGLQRRRFV QNALNGNGDP NNMDKAVKLY RKLKREITFH GAKEIALSYS
     AGALASCMGL IYNRMGAVTT EVAFGLVCAT CEQIADSQHR SHRQMVTTTN PLIRHENRMV
     LASTTAKAME QMAGSSEQAA EAMDIASQAR QMVQAMRTIG THPSSSAGLK DDLLENLQAY
     QKRMGVQMQR FK
//