ID I1TSE4_9HIV1 Unreviewed; 85 AA.
AC I1TSE4;
DT 11-JUL-2012, integrated into UniProtKB/TrEMBL.
DT 11-JUL-2012, sequence version 1.
DT 27-MAR-2024, entry version 37.
DE RecName: Full=Protein Vpu {ECO:0000256|ARBA:ARBA00018094, ECO:0000256|RuleBase:RU364058};
DE AltName: Full=U ORF protein {ECO:0000256|ARBA:ARBA00031215, ECO:0000256|RuleBase:RU364058};
DE AltName: Full=Viral protein U {ECO:0000256|ARBA:ARBA00030659, ECO:0000256|RuleBase:RU364058};
DE Flags: Fragment;
GN Name=vpu {ECO:0000256|RuleBase:RU364058, ECO:0000313|EMBL:AFH23339.1};
OS Human immunodeficiency virus 1.
OC Viruses; Riboviria; Pararnavirae; Artverviricota; Revtraviricetes;
OC Ortervirales; Retroviridae; Orthoretrovirinae; Lentivirus.
OX NCBI_TaxID=11676 {ECO:0000313|EMBL:AFH23339.1};
OH NCBI_TaxID=9606; Homo sapiens (Human).
RN [1] {ECO:0000313|EMBL:AFH23339.1}
RP NUCLEOTIDE SEQUENCE.
RC STRAIN=C.BW.2005.B.010.18 {ECO:0000313|EMBL:AFH23339.1};
RX PubMed=22590503; DOI=10.1371/journal.pone.0035491;
RA Rossenkhan R., Novitsky V., Sebunya T.K., Musonda R., Gashe B.A., Essex M.;
RT "Viral Diversity and Diversification of Major Non-Structural Genes vif,
RT vpr, vpu, tat exon 1 and rev exon 1 during Primary HIV-1 Subtype C
RT Infection.";
RL PLoS ONE 7:E35491-E35491(2012).
CC -!- FUNCTION: Enhances virion budding by targeting host CD4 and
CC Tetherin/BST2 to proteasome degradation. Degradation of CD4 prevents
CC any unwanted premature interactions between viral Env and its host
CC receptor CD4 in the endoplasmic reticulum. Degradation of
CC antiretroviral protein Tetherin/BST2 is important for virion budding,
CC as BST2 tethers new viral particles to the host cell membrane.
CC Mechanistically, Vpu bridges either CD4 or BST2 to BTRC, a substrate
CC recognition subunit of the Skp1/Cullin/F-box protein E3 ubiquitin
CC ligase, induces their ubiquitination and subsequent proteasomal
CC degradation. The alteration of the E3 ligase specificity by Vpu seems
CC to promote the degradation of host IKBKB, leading to NF-kappa-B down-
CC regulation and subsequent apoptosis. Acts as a viroporin that forms an
CC oligomeric ion channel in membranes. Modulates the host DNA repair
CC mechanisms to promote degradation of nuclear viral cDNA in cells that
CC are already productively infected in order to suppress immune sensing
CC and proviral hyper-integration (superinfection). Manipulates PML-NBs
CC and modulates SUMOylation of host BLM protein thereby enhancing its
CC DNA-end processing activity toward viral unintegrated linear DNA. Also
CC inhibits RAD52-mediated homologous repair of viral cDNA, preventing the
CC generation of dead-end circular forms of single copies of the long
CC terminal repeat and permitting sustained nucleolytic attack.
CC {ECO:0000256|RuleBase:RU364058}.
CC -!- SUBCELLULAR LOCATION: Host membrane {ECO:0000256|RuleBase:RU364058};
CC Single-pass type I membrane protein {ECO:0000256|RuleBase:RU364058}.
CC -!- SIMILARITY: Belongs to the HIV-1 VPU protein family.
CC {ECO:0000256|RuleBase:RU364058}.
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; JQ895592; AFH23339.1; -; Genomic_RNA.
DR GO; GO:0033644; C:host cell membrane; IEA:UniProtKB-SubCell.
DR GO; GO:0016020; C:membrane; IEA:UniProtKB-SubCell.
DR GO; GO:0042609; F:CD4 receptor binding; IEA:InterPro.
DR GO; GO:0005261; F:monoatomic cation channel activity; IEA:InterPro.
DR GO; GO:0032801; P:receptor catabolic process; IEA:InterPro.
DR GO; GO:0019076; P:viral release from host cell; IEA:UniProtKB-UniRule.
DR Gene3D; 1.10.195.10; HIV-1 VPU cytoplasmic domain; 1.
DR HAMAP; MF_04082; HIV_VPU; 1.
DR InterPro; IPR008187; Vpu.
DR InterPro; IPR009032; Vpu_cyt_dom_sf.
DR Pfam; PF00558; Vpu; 1.
DR SUPFAM; SSF57647; HIV-1 VPU cytoplasmic domain; 1.
PE 3: Inferred from homology;
KW Apoptosis {ECO:0000256|RuleBase:RU364058};
KW Host membrane {ECO:0000256|RuleBase:RU364058};
KW Host-virus interaction {ECO:0000256|RuleBase:RU364058};
KW Ion channel {ECO:0000256|RuleBase:RU364058};
KW Ion transport {ECO:0000256|RuleBase:RU364058};
KW Membrane {ECO:0000256|RuleBase:RU364058};
KW Transmembrane {ECO:0000256|RuleBase:RU364058};
KW Transmembrane helix {ECO:0000256|RuleBase:RU364058};
KW Transport {ECO:0000256|RuleBase:RU364058}.
FT TRANSMEM 12..33
FT /note="Helical"
FT /evidence="ECO:0000256|RuleBase:RU364058"
FT NON_TER 85
FT /evidence="ECO:0000313|EMBL:AFH23339.1"
SQ SEQUENCE 85 AA; 9838 MW; 56C5273F95847D20 CRC64;
MINLQAEVDY RIGIAAFVVA LIIAIIVWTI VYIEYRKLVK QRKIDRLIKR IRERAEDSGN
ESEGDNEELA AMVDMGQLRL FDVND
//