ID   AGNO_POVBA              Reviewed;          74 AA.
AC   P14998;
DT   01-APR-1990, integrated into UniProtKB/Swiss-Prot.
DT   01-APR-1990, sequence version 1.
DT   07-APR-2021, entry version 64.
DE   RecName: Full=Agnoprotein;
DE   AltName: Full=Agno;
OS   BK polyomavirus (strain AS) (BKPyV).
OC   Viruses; Monodnaviria; Shotokuvirae; Cossaviricota; Papovaviricetes;
OC   Sepolyvirales; Polyomaviridae; Betapolyomavirus.
OX   NCBI_TaxID=10631;
OH   NCBI_TaxID=9606; Homo sapiens (Human).
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX   PubMed=2536111; DOI=10.1128/jvi.63.2.901-911.1989;
RA   Tavis J.E., Walker D.L., Gardner S.D., Frisque R.J.;
RT   "Nucleotide sequence of the human polyomavirus AS virus, an antigenic
RT   variant of BK virus.";
RL   J. Virol. 63:901-911(1989).
CC   -!- FUNCTION: Alters the structure of the nuclear envelope by interacting
CC       with host CBX5 and disrupting CBX5 association with LBR. Involved in
CC       the perinuclear-nuclear localization of the capsid protein VP1 during
CC       virion assembly and maturation. Plays an important role in the release
CC       of progeny virions from infected cells and in viral propagation,
CC       probably by acting as a viral ionic channel in the host plasma
CC       membrane. Allows influx of extracellular calcium ions in the host cell.
CC       May contribute to viral genome transcription and translation of viral
CC       late proteins (By similarity). {ECO:0000250}.
CC   -!- SUBUNIT: Homooligomer. Interacts with VP1 (By similarity). Interacts
CC       with large T antigen; this interaction may impact upon the activity of
CC       T-antigen on the control of viral gene transcription and replication.
CC       Interacts with small t antigen. Interacts with host CBX5; this
CC       interaction induces the dissociation of CBX5 from LBR, resulting in
CC       destabilization of the nuclear envelope (By similarity). {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Host cytoplasm {ECO:0000305}. Host nucleus
CC       membrane {ECO:0000305}; Single-pass type II membrane protein
CC       {ECO:0000305}. Host rough endoplasmic reticulum membrane {ECO:0000305};
CC       Single-pass type II membrane protein {ECO:0000305}. Host cell membrane
CC       {ECO:0000305}; Single-pass type II membrane protein {ECO:0000305}.
CC       Note=Mostly perinuclear. {ECO:0000250}.
CC   -!- ALTERNATIVE PRODUCTS:
CC       Event=Alternative splicing, Alternative initiation; Named isoforms=5;
CC       Name=Agno;
CC         IsoId=P14998-1; Sequence=Displayed;
CC       Name=VP2; Synonyms=Minor capsid protein VP2;
CC         IsoId=P14997-1; Sequence=External;
CC       Name=VP3; Synonyms=Minor capsid protein VP3;
CC         IsoId=P14997-2; Sequence=External;
CC       Name=VP4; Synonyms=Viroporin VP4;
CC         IsoId=P14997-3; Sequence=External;
CC       Name=VP1;
CC         IsoId=P14996-1; Sequence=External;
CC   -!- PTM: Phosphorylated by host kinase. Phosphorylation segregates
CC       agnoprotein in cytoplasm, whereas unphosphorylated agnoprotein migrate
CC       to the nucleus (By similarity). {ECO:0000250}.
CC   -!- MISCELLANEOUS: [Isoform Agno]: Produced by alternative initiation of
CC       the late mRNA.
CC   -!- SIMILARITY: Belongs to the polyomavirus agnoprotein family.
CC       {ECO:0000305}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; M23122; AAA46879.1; -; Genomic_DNA.
DR   PIR; C33278; DNVPAS.
DR   SMR; P14998; -.
DR   Proteomes; UP000008166; Genome.
DR   GO; GO:0044200; C:host cell nuclear membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0020002; C:host cell plasma membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0044169; C:host cell rough endoplasmic reticulum membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR   GO; GO:0044385; C:integral to membrane of host cell; IEA:UniProtKB-KW.
DR   GO; GO:0003677; F:DNA binding; IEA:InterPro.
DR   GO; GO:0005216; F:ion channel activity; IEA:UniProtKB-KW.
DR   GO; GO:0039707; P:pore formation by virus in membrane of host cell; IEA:UniProtKB-KW.
DR   GO; GO:0051259; P:protein complex oligomerization; IEA:UniProtKB-KW.
DR   InterPro; IPR002643; Polyoma_agno.
DR   Pfam; PF01736; Polyoma_agno; 1.
PE   3: Inferred from homology;
KW   Alternative initiation; Alternative splicing; Host cell membrane;
KW   Host cytoplasm; Host endoplasmic reticulum; Host membrane; Host nucleus;
KW   Host-virus interaction; Ion channel; Ion transport; Membrane;
KW   Phosphoprotein; Signal-anchor; Transmembrane; Transmembrane helix;
KW   Transport; Viral ion channel.
FT   CHAIN           1..74
FT                   /note="Agnoprotein"
FT                   /id="PRO_0000115030"
FT   TOPO_DOM        1..35
FT                   /note="Cytoplasmic"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        36..52
FT                   /note="Helical; Signal-anchor for type II membrane protein"
FT                   /evidence="ECO:0000255"
FT   TOPO_DOM        53..74
FT                   /note="Extracellular"
FT                   /evidence="ECO:0000255"
FT   MOD_RES         15
FT                   /note="Phosphoserine; by host"
FT                   /evidence="ECO:0000250"
FT   MOD_RES         19
FT                   /note="Phosphoserine; by host"
FT                   /evidence="ECO:0000250"
FT   MOD_RES         29
FT                   /note="Phosphothreonine; by host"
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   74 AA;  8328 MW;  B77365F6878718BB CRC64;
     MFCEPKNLVV LRQLSRQASV KVGKTWTGTK KRAQRIFIFI LELLLEFCRG EDSVDGKNKS
     TTALPAVKDS VKDS