1pi8

From Proteopedia

(Difference between revisions)

Revision as of 15:14, 27 October 2021

Structure of the channel-forming trans-membrane domain of Virus protein "u" (Vpu) from HIV-1

Structural highlights

1pi8 is a 1 chain structure with sequence from 9hiv1. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	1pi7
Gene:	VPU (9HIV1)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[VPU_HV1LW] Enhances virion budding, by targeting human CD4 and Tetherin/BST2 to proteasome degradation. Degradation of CD4 prevents any unwanted premature interactions between viral Env and its receptor human 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 interfere with the degradation of host IKBKB, leading to NF-kappa-B down-regulation and subsequent apoptosis. Ion channel activity has also been suggested, however, formation of cation-selective channel has been reconstituted ex-vivo in lipid bilayers. It is thus unsure that this activity plays a role in vivo (By similarity).

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The three-dimensional structure of the channel-forming trans-membrane domain of virus protein "u" (Vpu) of HIV-1 was determined by NMR spectroscopy in micelle and bilayer samples. Vpu(2-30+) is a 36-residue polypeptide that consists of residues 2-30 from the N terminus of Vpu and a six-residue "solubility tag" at its C terminus that facilitates the isolation, purification, and sample preparation of this highly hydrophobic minimal channel-forming domain. Nearly all of the resonances in the two-dimensional 1H/15N HSQC spectrum of uniformly 15N labeled Vpu(2-30+) in micelles are superimposable on those from the corresponding residues in the spectrum of full-length Vpu, which indicates that the structure of the trans-membrane domain is not strongly affected by the presence of the cytoplasmic domain at its C terminus. The two-dimensional 1H/15N PISEMA spectrum of Vpu(2-30+) in lipid bilayers aligned between glass plates has been fully resolved and assigned. The "wheel-like" pattern of resonances in the spectrum is characteristic of a slightly tilted membrane-spanning helix. Experiments were also performed on weakly aligned micelle samples to measure residual dipolar couplings and chemical shift anisotropies. The analysis of the PISA wheels and Dipolar Waves obtained from both weakly and completely aligned samples show that Vpu(2-30+) has a trans-membrane alpha-helix spanning residues 8-25 with an average tilt of 13 degrees. The helix is kinked slightly at Ile17, which results in tilts of 12 degrees for residues 8-16 and 15 degrees for residues 17-25. A structural fit to the experimental solid-state NMR data results in a three-dimensional structure with precision equivalent to an RMSD of 0.4 A. Vpu(2-30+) exists mainly as an oligomer on PFO-PAGE and forms ion-channels, a most frequent conductance of 96(+/- 6) pS in lipid bilayers. The structural features of the trans-membrane domain are determinants of the ion-channel activity that may be associated with the protein's role in facilitating the budding of new virus particles from infected cells.

Three-dimensional structure of the channel-forming trans-membrane domain of virus protein "u" (Vpu) from HIV-1.,Park SH, Mrse AA, Nevzorov AA, Mesleh MF, Oblatt-Montal M, Montal M, Opella SJ J Mol Biol. 2003 Oct 17;333(2):409-24. PMID:14529626^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Park SH, Mrse AA, Nevzorov AA, Mesleh MF, Oblatt-Montal M, Montal M, Opella SJ. Three-dimensional structure of the channel-forming trans-membrane domain of virus protein "u" (Vpu) from HIV-1. J Mol Biol. 2003 Oct 17;333(2):409-24. PMID:14529626

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1pi8"

@@ Line 3: / Line 3: @@
 <StructureSection load='1pi8' size='340' side='right'caption='[[1pi8]], [[NMR_Ensembles_of_Models | 4 NMR models]]' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[1pi8]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/9hiv1 9hiv1]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PI8 OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=1PI8 FirstGlance]. <br>
+<table><tr><td colspan='2'>[[1pi8]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/9hiv1 9hiv1]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PI8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1PI8 FirstGlance]. <br>
 </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1pi7|1pi7]]</div></td></tr>
-<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">VPU ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=11676 9HIV1])</td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">VPU ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=11676 9HIV1])</td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=1pi8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1pi8 OCA], [http://pdbe.org/1pi8 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1pi8 RCSB], [http://www.ebi.ac.uk/pdbsum/1pi8 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1pi8 ProSAT]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1pi8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1pi8 OCA], [https://pdbe.org/1pi8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1pi8 RCSB], [https://www.ebi.ac.uk/pdbsum/1pi8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1pi8 ProSAT]</span></td></tr>
 </table>
 == Function ==
-[[http://www.uniprot.org/uniprot/VPU_HV1LW VPU_HV1LW]] Enhances virion budding, by targeting human CD4 and Tetherin/BST2 to proteasome degradation. Degradation of CD4 prevents any unwanted premature interactions between viral Env and its receptor human 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 interfere with the degradation of host IKBKB, leading to NF-kappa-B down-regulation and subsequent apoptosis. Ion channel activity has also been suggested, however, formation of cation-selective channel has been reconstituted ex-vivo in lipid bilayers. It is thus unsure that this activity plays a role in vivo (By similarity).
+[[https://www.uniprot.org/uniprot/VPU_HV1LW VPU_HV1LW]] Enhances virion budding, by targeting human CD4 and Tetherin/BST2 to proteasome degradation. Degradation of CD4 prevents any unwanted premature interactions between viral Env and its receptor human 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 interfere with the degradation of host IKBKB, leading to NF-kappa-B down-regulation and subsequent apoptosis. Ion channel activity has also been suggested, however, formation of cation-selective channel has been reconstituted ex-vivo in lipid bilayers. It is thus unsure that this activity plays a role in vivo (By similarity).
 == Evolutionary Conservation ==
 [[Image:Consurf_key_small.gif|200px|right]]
@@ Line 31: / Line 31: @@
 ==See Also==
-*[[HIV and accessory proteins|HIV and accessory proteins]]
 *[[Vpu protein|Vpu protein]]
 == References ==

1pi8

From Proteopedia

Revision as of 15:14, 27 October 2021

Structure of the channel-forming trans-membrane domain of Virus protein "u" (Vpu) from HIV-1

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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