ID U3LJT6_9HIV1 Unreviewed; 81 AA. AC U3LJT6; DT 11-DEC-2013, integrated into UniProtKB/TrEMBL. DT 11-DEC-2013, sequence version 1. DT 07-JUN-2017, entry version 10. 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:AFZ63161.1}; OS Human immunodeficiency virus 1. OC Viruses; Retro-transcribing viruses; Retroviridae; Orthoretrovirinae; OC Lentivirus; Primate lentivirus group. OX NCBI_TaxID=11676 {ECO:0000313|EMBL:AFZ63161.1}; OH NCBI_TaxID=9606; Homo sapiens (Human). RN [1] {ECO:0000313|EMBL:AFZ63161.1} RP NUCLEOTIDE SEQUENCE. RC STRAIN=306336_ENV {ECO:0000313|EMBL:AFZ63161.1}; RA Heipertz R.Jr., Sanders-Buell E., Kijak G., Howell S., Lazzaro M., RA Jagodzinski L., Eggleston J., Peel S., Malia J., Armstrong A., RA Michael N., Kim J., O'Connell R., Scott P., Brett-Major D., RA Tovanabutra S.; RL Submitted (SEP-2012) to the EMBL/GenBank/DDBJ databases. RN [2] {ECO:0000313|EMBL:AFZ63161.1} RP NUCLEOTIDE SEQUENCE. RC STRAIN=306336_ENV {ECO:0000313|EMBL:AFZ63161.1}; RX PubMed=23972100; DOI=10.1089/AID.2013.0087; RA Heipertz R.A.Jr., Sanders-Buell E., Kijak G., Howell S., Lazzaro M., RA Jagodzinski L.L., Eggleston J., Peel S., Malia J., Armstrong A., RA Michael N.L., Kim J.H., O'Connell R.J., Scott P.T., Brett-Major D.M., RA Tovanabutra S.; RT "Molecular Epidemiology of Early and Acute HIV Type 1 Infections in RT the United States Navy and Marine Corps, 2005-2010."; RL AIDS Res. Hum. Retroviruses 29:1310-1320(2013). CC -!- FUNCTION: Enhances virion budding, by targeting human CD4 and CC Tetherin/BST2 to proteasome degradation. Degradation of CD4 CC prevents any unwanted premature interactions between viral Env and CC its receptor human CD4 in the endoplasmic reticulum. Degradation CC of 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; JX863994; AFZ63161.1; -; Genomic_RNA. DR GO; GO:0033644; C:host cell membrane; IEA:InterPro. 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:InterPro. DR Gene3D; 1.10.195.10; -; 1. DR InterPro; IPR008187; Vpu. DR InterPro; IPR009032; Vpu_cyt. 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; 9235 MW; E7638D28F224EC76 CRC64; MQSLQIAAII ALVVVAIIAI VVWSIILIEY RKILRQRKID RLIDRIRERA EDSGNESDGD QEELSGLVER GHLAPWDIDD L //