Q90MJ4 · Q90MJ4_HV1

Function

function

Enhances virion budding by targeting host CD4 and Tetherin/BST2 to proteasome degradation. Degradation of CD4 prevents any unwanted premature interactions between viral Env and its host receptor CD4 in the endoplasmic reticulum. Degradation of antiretroviral protein Tetherin/BST2 is important for virion budding, as BST2 tethers new viral particles to the host cell membrane. Mechanistically, Vpu bridges either CD4 or BST2 to BTRC, a substrate recognition subunit of the Skp1/Cullin/F-box protein E3 ubiquitin ligase, induces their ubiquitination and subsequent proteasomal degradation. The alteration of the E3 ligase specificity by Vpu seems to promote the degradation of host IKBKB, leading to NF-kappa-B down-regulation and subsequent apoptosis. Acts as a viroporin that forms an oligomeric ion channel in membranes. Modulates the host DNA repair mechanisms to promote degradation of nuclear viral cDNA in cells that are already productively infected in order to suppress immune sensing and proviral hyper-integration (superinfection). Manipulates PML-NBs and modulates SUMOylation of host BLM protein thereby enhancing its DNA-end processing activity toward viral unintegrated linear DNA. Also inhibits RAD52-mediated homologous repair of viral cDNA, preventing the generation of dead-end circular forms of single copies of the long terminal repeat and permitting sustained nucleolytic attack.

GO annotations

all annotationsall molecular functionvirus receptor activitydna bindingrna bindingcytoskeletal motor activitycatalytic activitygtpase activitystructural molecule activitytransporter activitycytoskeletal protein bindinglipid bindingcyclase activityantioxidant activityoxidoreductase activitytransferase activityhydrolase activitylyase activityisomerase activityligase activityprotein tag activitycargo receptor activityhistone bindingprotein folding chaperonetranslation regulator activitynutrient reservoir activityreceptor ligand activitymolecular transducer activitymolecular adaptor activitytoxin activitycell adhesion mediator activitymolecular function regulator activityvirus coreceptor activitycatalytic activity, acting on a proteincatalytic activity, acting on dnacatalytic activity, acting on rnamolecular carrier activitytranscription regulator activitygeneral transcription initiation factor activitymolecular sensor activitymolecular sequestering activityatp-dependent activityother molecular functionall biological processmitotic cell cyclecytokinesiscytoplasmic translationimmune system processmuscle system processcirculatory system processrenal system processrespiratory system processcarbohydrate metabolic processgeneration of precursor metabolites and energydna replicationdna repairdna recombinationchromatin organizationdna-templated transcriptionregulation of dna-templated transcriptiontrna metabolic processprotein foldingprotein glycosylationamino acid metabolic processmodified amino acid metabolic processlipid metabolic processvitamin metabolic processsulfur compound metabolic processintracellular protein transportnucleocytoplasmic transportautophagyinflammatory responsemitochondrion organizationcytoskeleton organizationmicrotubule-based movementperoxisome organizationlysosome organizationchromosome segregationcell adhesionestablishment or maintenance of cell polarityprogrammed cell deathphotosynthesismrna metabolic processsnrna metabolic processvesicle-mediated transportreproductive processdigestive system processsignalingcell differentiationprotein catabolic processextracellular matrix organizationregulatory ncrna-mediated gene silencingtelomere organizationcell junction organizationwound healingribosome biogenesiscilium organizationanatomical structure developmentcell motilitynervous system processendocrine processprotein maturationtransmembrane transportnucleobase-containing small molecule metabolic processhepaticobiliary system processmembrane organizationprotein-containing complex assemblycell wall organization or biogenesisnitrogen cycle metabolic processprotein localization to plasma membranedefense response to other organismdetoxificationmeiotic nuclear divisionmitotic nuclear divisionmitochondrial gene expressioncarbohydrate derivative metabolic processother biological processall cellular componentnuclear chromosomeextracellular regionextracellular spacecell wallnucleusnuclear envelopenucleoplasmchromosomenucleolusmitochondrionlysosomeendosomevacuoleperoxisomeendoplasmic reticulumgolgi apparatuslipid dropletmicrotubule organizing centercytosolribosomecytoskeletonplasma membraneciliumplastidthylakoidexternal encapsulating structureextracellular matrixcytoplasmic vesicleorganelleother cellular component
Cell color indicative of number of GO terms
AspectTerm
Cellular Componenthost cell membrane
Cellular Componentmembrane
Molecular FunctionCD4 receptor binding
Molecular Functionmonoatomic cation channel activity
Biological Processapoptotic process
Biological Processreceptor catabolic process
Biological Processviral release from host cell

Keywords

Names & Taxonomy

Protein names

  • Recommended name
    Protein Vpu
  • Alternative names
    • U ORF protein
    • Viral protein U

Gene names

    • Name
      vpu

Organism names

Accessions

  • Primary accession
    Q90MJ4

Subcellular Location

Host membrane
; Single-pass type I membrane protein

Features

Showing features for transmembrane.

TypeIDPosition(s)Description
Transmembrane6-28Helical

Keywords

Family & Domains

Sequence similarities

Belongs to the HIV-1 VPU protein family.

Keywords

Family and domain databases

Sequence

  • Sequence status
    Fragment
  • Length
    82
  • Mass (Da)
    9,311
  • Last updated
    2001-12-01 v1
  • Checksum
    D22EEA504BB4BA85
MQPLVIAAIVALVVVGIIAIIVWSIVLIEYRKILRQRRIDRLIDRIRERAEDSGNESEGDQEELSALVEVGQHLEMGHLAPW

Features

Showing features for non-terminal residue.

TypeIDPosition(s)Description
Non-terminal residue82

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AF387053
EMBL· GenBank· DDBJ
AAK68088.1
EMBL· GenBank· DDBJ
Genomic DNA

Similar Proteins

Disclaimer

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