| Structural highlights
Function
[PDC6I_HUMAN] Class E VPS protein involved in concentration and sorting of cargo proteins of the multivesicular body (MVB) for incorporation into intralumenal vesicles (ILVs) that are generated by invagination and scission from the limiting membrane of the endosome. Binds to the phospholipid lysobisphosphatidic acid (LBPA) which is abundant in MVBs internal membranes. The MVB pathway appears to require the sequential function of ESCRT-O, -I,-II and -III complexes. The ESCRT machinery also functions in topologically equivalent membrane fission events, such as the terminal stages of cytokinesis and enveloped virus budding (HIV-1 and other lentiviruses). Appears to be an adapter for a subset of ESCRT-III proteins, such as CHMP4, to function at distinct membranes. Required for completion of cytokinesis. Involved in HIV-1 virus budding. Can replace TSG101 it its role of supporting HIV-1 release; this function implies the interaction with CHMP4B. May play a role in the regulation of both apoptosis and cell proliferation.[1] [2] [3] [4] [5] [6]
Publication Abstract from PubMed
Retroviral Gag proteins contain short late domain motifs that recruit cellular ESCRT pathway proteins to facilitate virus budding. ALIX-binding late domains often contain the core consensus sequence: "YPXnL" (where Xn can vary in sequence and length). However, some SIV Gag proteins lack this consensus sequence, yet still bind ALIX. We mapped divergent, ALIX-binding late domains within the p6(Gag) proteins of SIVmac239 (40SREKPYKEVTEDLLHLNSLF59) and SIVagmTan-1 (24AAGAYDPARKLLEQYAKK41). Crystal structures revealed that anchoring tyrosines (bold) and nearby hydrophobic residues (underlined) contact the ALIX V domain, revealing how lentiviruses employ a diverse family of late domain sequences to bind ALIX and promote virus budding.
Identification and Structural Characterization of the ALIX-Binding Late Domains of SIVmac239 and SIVagmTan-1.,Zhai Q, Landesman M, Robinson H, Sundquist WI, Hill CP J Virol. 2010 Oct 20. PMID:20962096[7]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Strack B, Calistri A, Craig S, Popova E, Gottlinger HG. AIP1/ALIX is a binding partner for HIV-1 p6 and EIAV p9 functioning in virus budding. Cell. 2003 Sep 19;114(6):689-99. PMID:14505569
- ↑ von Schwedler UK, Stuchell M, Muller B, Ward DM, Chung HY, Morita E, Wang HE, Davis T, He GP, Cimbora DM, Scott A, Krausslich HG, Kaplan J, Morham SG, Sundquist WI. The protein network of HIV budding. Cell. 2003 Sep 19;114(6):701-13. PMID:14505570
- ↑ Matsuo H, Chevallier J, Mayran N, Le Blanc I, Ferguson C, Faure J, Blanc NS, Matile S, Dubochet J, Sadoul R, Parton RG, Vilbois F, Gruenberg J. Role of LBPA and Alix in multivesicular liposome formation and endosome organization. Science. 2004 Jan 23;303(5657):531-4. PMID:14739459 doi:10.1126/science.1092425
- ↑ Morita E, Sandrin V, Chung HY, Morham SG, Gygi SP, Rodesch CK, Sundquist WI. Human ESCRT and ALIX proteins interact with proteins of the midbody and function in cytokinesis. EMBO J. 2007 Oct 3;26(19):4215-27. Epub 2007 Sep 13. PMID:17853893 doi:10.1038/sj.emboj.7601850
- ↑ Usami Y, Popov S, Gottlinger HG. Potent rescue of human immunodeficiency virus type 1 late domain mutants by ALIX/AIP1 depends on its CHMP4 binding site. J Virol. 2007 Jun;81(12):6614-22. Epub 2007 Apr 11. PMID:17428861 doi:10.1128/JVI.00314-07
- ↑ Carlton JG, Martin-Serrano J. Parallels between cytokinesis and retroviral budding: a role for the ESCRT machinery. Science. 2007 Jun 29;316(5833):1908-12. Epub 2007 Jun 7. PMID:17556548 doi:10.1126/science.1143422
- ↑ Zhai Q, Landesman M, Robinson H, Sundquist WI, Hill CP. Identification and Structural Characterization of the ALIX-Binding Late Domains of SIVmac239 and SIVagmTan-1. J Virol. 2010 Oct 20. PMID:20962096 doi:10.1128/JVI.01683-10
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