ID Q8AEH0_9HIV1 Unreviewed; 81 AA. AC Q8AEH0; DT 01-MAR-2003, integrated into UniProtKB/TrEMBL. DT 01-MAR-2003, sequence version 1. DT 12-SEP-2018, entry version 46. DE RecName: Full=Protein Vpu {ECO:0000256|RuleBase:RU364058}; DE AltName: Full=U ORF protein {ECO:0000256|RuleBase:RU364058}; DE AltName: Full=Viral protein U {ECO:0000256|RuleBase:RU364058}; GN Name=vpu {ECO:0000256|RuleBase:RU364058, ECO:0000313|EMBL:CAD26741.1}; OS Human immunodeficiency virus 1. OC Viruses; Ortervirales; Retroviridae; Orthoretrovirinae; Lentivirus. OX NCBI_TaxID=11676 {ECO:0000313|EMBL:CAD26741.1}; OH NCBI_TaxID=9606; Homo sapiens (Human). RN [1] {ECO:0000313|EMBL:CAD26741.1} RP NUCLEOTIDE SEQUENCE. RA Saurya S.; RT "Molecular characterization of HIV-1 from HAARt treated AIDS patients RT with discordance between viral load and CD4+ T cell counts."; RL Thesis (2002), Department of Haematological Medicine, Cambridge RL University, Cambridge, United Kingdom. CC -!- FUNCTION: Enhances virion budding by targeting host CD4 and CC Tetherin/BST2 to proteasome degradation. Degradation of CD4 CC prevents any unwanted premature interactions between viral Env and CC its host receptor CD4 in the endoplasmic reticulum. Degradation of CC antiretroviral protein Tetherin/BST2 is important for virion CC budding, as BST2 tethers new viral particles to the host cell CC membrane. Mechanistically, Vpu bridges either CD4 or BST2 to BTRC, CC a substrate recognition subunit of the Skp1/Cullin/F-box protein CC E3 ubiquitin ligase, induces their ubiquitination and subsequent CC proteasomal degradation. The alteration of the E3 ligase CC specificity by Vpu seems to promote the degradation of host IKBKB, CC leading to NF-kappa-B down-regulation and subsequent apoptosis. CC Ion channel activity has also been suggested, however, formation CC of cation-selective channel has been reconstituted ex-vivo in CC lipid bilayers. It is thus unsure that this activity plays a role CC in vivo. {ECO:0000256|RuleBase:RU364058}. CC -!- SUBCELLULAR LOCATION: Host membrane CC {ECO:0000256|RuleBase:RU364058}; Single-pass type I membrane CC 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; AJ437518; CAD26741.1; -; Genomic_RNA. DR ProteinModelPortal; Q8AEH0; -. DR GO; GO:0033644; C:host cell membrane; IEA:UniProtKB-SubCell. DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW. DR GO; GO:0005261; F:cation channel activity; IEA:InterPro. DR GO; GO:0042609; F:CD4 receptor binding; 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; -; 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; SSF57647; 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 6 28 Helical. {ECO:0000256|RuleBase:RU364058}. SQ SEQUENCE 81 AA; 9136 MW; 88A62E9E2C0630A3 CRC64; MQPLVIGAIV ALVIAIIIAI VVWSIVLIEY RKILRQRKID RLIDRIRERA EDSGNESEGD QDELSTLVGM GHDAPWDVND L //