P03093 · VP2_SV40

  • Protein
    Minor capsid protein VP2
  • Status
    UniProtKB reviewed (Swiss-Prot)
  • Amino acids
  • Protein existence
    Evidence at protein level
  • Annotation score
    5/5

Function

function

Isoform VP2

Structural protein that resides within the core of the capsid surrounded by 72 VP1 pentamers. Following virus endocytosis and trafficking to the endoplasmic reticulum, VP2 and VP3 form oligomers and integrate into the endoplasmic reticulum membrane. Heterooligomer VP2-VP3 may create a viroporin for transporting the viral genome across the endoplasmic reticulum membrane to the cytoplasm. Nuclear entry of the viral DNA involves the selective exposure and importin recognition of VP2 or VP3 nuclear localization signal (shared C-terminus). Plays a role in virion assembly within the nucleus in particular through a DNA-binding domain located in the C-terminal region. A N-terminal myristoylation suggests a scaffold function for virion assembly. The viral progenies exit the cells by lytic release. Isoform VP2 may repress SP1 activation of the SV40 early promoter, via specific protein-protein and protein-DNA interactions.

Isoform VP3

Structural protein that resides within the core of the capsid surrounded by 72 VP1 pentamers. Following virus entry, VP2 and VP3 form oligomers and integrate into the endoplasmic reticulum membrane. Heterooligomer VP2-VP3 may create a viroporin for transporting the viral genome across the endoplasmic reticulum membrane. Essential for focus formation and virus endoplasmic reticulum-to-cytosol membrane transport, required to recruit selective cellular components to the foci in the ER membrane. Nuclear entry of the viral DNA involves the selective exposure and importin recognition of VP2 or VP3 nuclear localization signal (shared C-terminus). Isoform VP3 represses SP1 activation of the SV40 early promoter, via specific protein-protein and protein-DNA interactions. SP1 additionally participates in recruiting VP3 to the SV40 minichromosome during SV40 assembly. Plays a role in virion assembly within the nucleus. May initiate host cell lysis when associated with VP4.

Isoform VP4

Viroporin inducing perforation of cellular membranes to trigger virus progeny release. Forms pores of 3 nm inner diameter. VP4 is expressed about 24 hours after the late structural proteins and is not incorporated into the mature virion.

GO annotations

AspectTerm
Cellular Componenthost cell
Cellular Componenthost cell endoplasmic reticulum membrane
Cellular Componenthost cell nucleus
Cellular Componentmembrane
Cellular Componentviral capsid
Molecular Functionchannel activity
Molecular FunctionDNA binding
Molecular Functionstructural molecule activity
Biological Processmonoatomic ion transmembrane transport
Biological Processsymbiont entry into host cell via permeabilization of host membrane
Biological Processviral penetration into host nucleus
Biological Processvirion attachment to host cell

Keywords

Protein family/group databases

Names & Taxonomy

Protein names

  • Recommended name
    Minor capsid protein VP2
  • Alternative names
    • Minor structural protein VP2

Organism names

Accessions

  • Primary accession
    P03093

Proteomes

Subcellular Location

Isoform VP2

Virion
Host nucleus
Note: Following host cell entry, the virion enters into the endoplasmic reticulum through a calveolar-dependent pathway. Then, isoform VP2 integrates into the endoplasmic reticulum membrane and participates in the translocation of viral DNA to the nucleus. Shortly after synthesis, a nuclear localization signal directs isoform VP2 to the cell nucleus where virion assembly occurs.

Isoform VP3

Virion
Host nucleus
Note: Following host cell entry, the virion enters into the endoplasmic reticulum through a calveolar-dependent pathway. Then, isoform VP3 integrates into the endoplasmic reticulum membrane and participates in the translocation of viral DNA to the nucleus. Shortly after synthesis, a nuclear localization signal directs isoform VP3 to the cell nucleus where virion assembly occurs.

Isoform VP4

Host nucleus

Features

Showing features for transmembrane.

TypeIDPosition(s)Description
Transmembrane290-310Helical

Keywords

Phenotypes & Variants

Features

Showing features for natural variant, mutagenesis.

Type
IDPosition(s)Description
Natural variant63in strain: 776
Mutagenesis276-277Complete loss of interaction with VP1.
Mutagenesis283-285Complete loss of interaction with VP1.
Mutagenesis296Partial loss of interaction with VP1.
Mutagenesis300Partial loss of interaction with VP1.
Mutagenesis344Partial loss of DNA-binding activity.
Mutagenesis348Partial loss of DNA-binding activity.

Variants

We now provide the "Disease & Variants" viewer in its own tab.

The viewer provides 1 variant from UniProt as well as other sources including ClinVar and dbSNP.

Go to variant viewer

PTM/Processing

Features

Showing features for initiator methionine, lipidation, chain.

Type
IDPosition(s)Description
Initiator methionine1Removed; by host
Lipidation2N-myristoyl glycine; by host
ChainPRO_00000392232-352Minor capsid protein VP2

Keywords

PTM databases

Expression

Keywords

Interaction

Subunit

Isoform VP2

Forms homooligomers, and heterooligomers with VP3 in the endoplasmic reticulum membrane. Interacts (via D1 domain) with VP1.

Isoform VP3

Interacts (via D1 domain) with VP1 (PubMed:16940501).
Interacts (via C-terminus) with host SP1, this is probably also the case for VP2; this interaction represses SP1 activation of the SV40 early promoter and participates in virion assembly (PubMed:9466902).
Interacts (via nuclear localization signal) with host importin alpha2-beta heterodimer (PubMed:12186919).

Isoform VP4

Oligomerizes with VP3 in the nucleus.

Binary interactions

TypeEntry 1Entry 2Number of experimentsIntAct
BINARY P03093 P030873EBI-1555798, EBI-1555770

Protein-protein interaction databases

Family & Domains

Features

Showing features for region, motif, compositional bias.

Type
IDPosition(s)Description
Region273-308D1
Region313-352Disordered
Region313-352DNA-binding
Motif316-324Nuclear localization signal
Compositional bias337-352Basic residues

Domain

The D1 region of isoform VP2 and isoform VP3 is necessary and sufficient to direct the interaction with VP1.
The basic-rich C-terminal region of isoforms VP2 and VP3 is sufficient for DNA-binding and may cause compaction of the DNA.
The transmembrane region is only used when isoform VP2 and isoform VP3 form oligomers and integrate into the endoplasmic reticulum membrane.

Sequence similarities

Keywords

Family and domain databases

Sequence & Isoforms

Align isoforms (5)
  • Sequence status
    Complete

This entry describes 5 isoforms produced by Alternative splicing & Alternative initiation.

P03093-1

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.

  • Name
    VP2
  • Synonyms
    Minor capsid protein VP2
  • Note
    Produced by alternative splicing of the late mRNA (19s mRNA).
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Length
    352
  • Mass (Da)
    38,539
  • Last updated
    2007-01-23 v3
  • Checksum
    79A1C73604646923
MGAALTLLGDLIATVSEAAAATGFSVAEIAAGEAAAAIEVQLASVATVEGLTTSEAIAAIGLIPQAYAVISGAPAAIAGFAALLQTVTGVSAVAQVGYRFFSDWDHKVSTVGLYQQPGMAVDLYRPDDYYDILFPGVQTFVHSVQYLDPRHWGPTLFNAISQAFWRVIQNDIPRLTSQELERRTQRYLRDSLARFLEETTWTVINAPVNWYNSLQDYYSTLSPIRPTMVRQVANREGLQISFGHTYDNIDEADSIQQVTERWEAQSQSPNVQSGEFIEKFEAPGGANQRTAPQWMLPLLLGLYGSVTSALKAYEDGPNKKKRKLSRGSSQKTKGTSASAKARHKRRNRSSRS

P03093-2

  • Name
    VP3
  • Synonyms
    Minor capsid protein VP3
  • Note
    Produced by alternative initiation at Met-119 of isoform VP2.
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Differences from canonical

P03093-3

  • Name
    VP4
  • Synonyms
    Viroporin VP4
  • Note
    Produced by alternative initiation at Met-228 of isoform VP2.
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Differences from canonical

P03087-1

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
  • Name
    VP1
  • Synonyms
    Major capsid protein VP1
  • See also
    sequence in UniParc or sequence clusters in UniRef

P03084-1

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
  • Name
    Agno
  • See also
    sequence in UniParc or sequence clusters in UniRef

Features

Showing features for alternative sequence, compositional bias.

Type
IDPosition(s)Description
Alternative sequenceVSP_0189251-118in isoform VP3
Alternative sequenceVSP_0358921-227in isoform VP4
Compositional bias337-352Basic residues

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
J02400
EMBL· GenBank· DDBJ
AAB59921.1
EMBL· GenBank· DDBJ
Genomic DNA
J02400
EMBL· GenBank· DDBJ
AAB59922.1
EMBL· GenBank· DDBJ
Genomic DNA

Similar Proteins

Disclaimer

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