title: TRIM5α associates with proteasomal subunits in cells while in complex with HIV-1 virions.
abstract: BACKGROUND
  The TRIM5 proteins are cellular restriction factors that prevent retroviral infection in a species-specific manner. Multiple experiments indicate that restriction activity requires accessory host factors, including E2-enzymes. To better understand the mechanism of restriction, we conducted yeast-two hybrid screens to identify proteins that bind to two TRIM5 orthologues.
  
  
  RESULTS
  The only cDNAs that scored on repeat testing with both TRIM5 orthologues were the proteasome subunit PSMC2 and ubiquitin. Using co-immunoprecipitation assays, we demonstrated an interaction between TRIM5α and PSMC2, as well as numerous other proteasome subunits. Fluorescence microscopy revealed co-localization of proteasomes and TRIM5α cytoplasmic bodies. Forster resonance energy transfer (FRET) analysis indicated that the interaction between TRIM5 and PSMC2 was direct. Previous imaging experiments demonstrated that, when cells are challenged with fluorescently-labeled HIV-1 virions, restrictive TRIM5α orthologues assemble cytoplasmic bodies around incoming virion particles. Following virus challenge, we observed localization of proteasome subunits to rhTRIM5α cytoplasmic bodies that contained fluorescently labeled HIV-1 virions.
  
  
  CONCLUSIONS
  Taken together, the results presented here suggest that localization of the proteasome to TRIM5α cytoplasmic bodies makes an important contribution to TRIM5α-mediated restriction.
authors.affiliation: Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, USA.
authors.forename: Zana
authors.initials: Z
authors.lastname: Lukic
authors.forename: Stéphane
authors.initials: S
authors.lastname: Hausmann
authors.forename: Sarah
authors.initials: S
authors.lastname: Sebastian
authors.forename: Justin
authors.initials: J
authors.lastname: Rucci
authors.forename: Jaya
authors.initials: J
authors.lastname: Sastri
authors.forename: Seth L
authors.initials: SL
authors.lastname: Robia
authors.forename: Jeremy
authors.initials: J
authors.lastname: Luban
authors.forename: Edward M
authors.initials: EM
authors.lastname: Campbell
mesh_terms: D000074183:ATPases Associated with Diverse Cellular Activities; D000090103:Antiviral Restriction Factors; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D003593:Cytoplasm / Q000235:genetics / Q000378:metabolism / Q000821:virology; D004274:DNA, Recombinant / Q000235:genetics / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer; D015723:Gene Library; D057809:HEK293 Cells; D015658:HIV Infections / Q000378:metabolism / Q000821:virology; D015497:HIV-1 / Q000378:metabolism* / Q000472:pathogenicity; D006801:Humans; D047468:Immunoprecipitation; D008856:Microscopy, Fluorescence; D046988:Proteasome Endopeptidase Complex / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D025941:Protein Interaction Mapping / Q000379:methods; D013045:Species Specificity; D014162:Transfection; D000070584:Tripartite Motif Proteins; D020798:Two-Hybrid System Techniques; D025801:Ubiquitin / Q000235:genetics / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases; D054875:Ubiquitination
chemical_list: D000090103:Antiviral Restriction Factors; D002352:Carrier Proteins; D004274:DNA, Recombinant; D000070584:Tripartite Motif Proteins; D025801:Ubiquitin; C075363:PSMC2 protein, human; C477346:TRIM5 protein, human; D044767:Ubiquitin-Protein Ligases; D046988:Proteasome Endopeptidase Complex; D000074183:ATPases Associated with Diverse Cellular Activities
references.citation: Proc Natl Acad Sci U S A. 2006 May 9;103(19):7465-70
references.pmid: 16648264
references.citation: IUBMB Life. 2006 May-Jun;58(5-6):344-8
references.pmid: 16754329
references.citation: Nucleic Acids Res. 2002 Jan 15;30(2):E9
references.pmid: 11788735
references.citation: J Virol. 2005 Dec;79(24):15567-72
references.pmid: 16306627
references.citation: J Biol Chem. 2008 May 2;283(18):12202-11
references.pmid: 18287099
references.citation: J Cell Biol. 2008 Feb 11;180(3):549-61
references.pmid: 18250195
references.citation: Proc Natl Acad Sci U S A. 2004 Sep 7;101(36):13324-8
references.pmid: 15326303
references.citation: Mol Biol Cell. 2007 Jun;18(6):2102-11
references.pmid: 17392513
references.citation: Nature. 2004 Feb 26;427(6977):848-53
references.pmid: 14985764
references.citation: J Cell Biol. 2002 Nov 11;159(3):441-52
references.pmid: 12417576
references.citation: J Control Release. 2004 May 18;96(3):473-82
references.pmid: 15120903
references.citation: J Mol Biol. 2007 Oct 12;373(1):1-10
references.pmid: 17804016
references.citation: Retrovirology. 2005 Jun 20;2:40
references.pmid: 15967037
references.citation: J Mol Biol. 2000 Nov 10;303(5):643-53
references.pmid: 11061965
references.citation: Proc Natl Acad Sci U S A. 2011 Jan 11;108(2):534-9
references.pmid: 21187419
references.citation: J Biol Chem. 2008 Oct 24;283(43):28996-9003
references.pmid: 18708665
references.citation: Biophys J. 2004 Jun;86(6):3923-39
references.pmid: 15189889
references.citation: Nature. 2004 Jul 29;430(6999):569-73
references.pmid: 15243629
references.citation: Mol Immunol. 1987 May;24(5):495-501
references.pmid: 3657792
references.citation: Mol Cell. 2006 Dec 28;24(6):977-84
references.pmid: 17189198
references.citation: J Virol. 2006 Oct;80(19):9754-60
references.pmid: 16973579
references.citation: J Virol. 2010 Jun;84(12):5997-6006
references.pmid: 20357094
references.citation: Virology. 2006 Jun 5;349(2):300-15
references.pmid: 16472833
references.citation: Proc Natl Acad Sci U S A. 2006 Apr 4;103(14):5514-9
references.pmid: 16540544
references.citation: FEBS J. 2008 Apr;275(7):1540-1555
references.pmid: 18312418
references.citation: Nat Rev Mol Cell Biol. 2009 Feb;10(2):104-15
references.pmid: 19165213
references.citation: J Virol. 2004 Jun;78(11):5745-55
references.pmid: 15140972
references.citation: J Virol. 2007 Oct;81(19):10362-78
references.pmid: 17626085
references.citation: PLoS Pathog. 2008 May 23;4(5):e1000074
references.pmid: 18497858
references.citation: Int J Biochem Cell Biol. 2003 May;35(5):579-89
references.pmid: 12672451
references.citation: Methods. 2001 Jul;24(3):289-96
references.pmid: 11403577
references.citation: Biochem Biophys Res Commun. 1995 Dec 5;217(1):21-7
references.pmid: 8526912
references.citation: Virology. 2010 Sep 15;405(1):259-66
references.pmid: 20633914
references.citation: Biochem Biophys Res Commun. 2008 Sep 12;374(1):33-7
references.pmid: 18598672
references.citation: Cell. 1993 Nov 19;75(4):791-803
references.pmid: 8242750
references.citation: Nature. 2011 Apr 21;472(7343):361-5
references.pmid: 21512573
references.citation: J Biol Chem. 2011 Oct 28;286(43):37470-82
references.pmid: 21880738
references.citation: J Virol. 2011 Sep;85(17):8725-37
references.pmid: 21734049
references.citation: Virology. 2005 Dec 20;343(2):201-11
references.pmid: 16183097
references.citation: EMBO J. 2001 May 1;20(9):2140-51
references.pmid: 11331580
references.citation: Nat Cell Biol. 2010 Sep;12(9):863-75
references.pmid: 20711182