2jq9

Structural highlights

Function

[VPS4A_HUMAN] Involved in late steps of the endosomal multivesicular bodies (MVB) pathway. Recognizes membrane-associated ESCRT-III assemblies and catalyzes their disassembly, possibly in combination with membrane fission. Redistributes the ESCRT-III components to the cytoplasm for further rounds of MVB sorting. MVBs contain intraluminal vesicles (ILVs) that are generated by invagination and scission from the limiting membrane of the endosome and mostly are delivered to lysosomes enabling degradation of membrane proteins, such as stimulated growth factor receptors, lysosomal enzymes and lipids. In conjunction with the ESCRT machinery also appears to function in topologically equivalent membrane fission events, such as the terminal stages of cytokinesis and enveloped virus budding (HIV-1 and other lentiviruses). Involved in cytokinesis.^{[1] [2] [3]} [CHM1A_HUMAN] Probable peripherally associated component of the endosomal sorting required for transport complex III (ESCRT-III) which is involved in multivesicular bodies (MVBs) formation and sorting of endosomal cargo proteins into MVBs. MVBs contain intraluminal vesicles (ILVs) that are generated by invagination and scission from the limiting membrane of the endosome and mostly are delivered to lysosomes enabling degradation of membrane proteins, such as stimulated growth factor receptors, lysosomal enzymes and lipids. The MVB pathway appears to require the sequential function of ESCRT-O, -I,-II and -III complexes. ESCRT-III proteins mostly dissociate from the invaginating membrane before the ILV is released. The ESCRT machinery also functions in topologically equivalent membrane fission events, such as the terminal stages of cytokinesis and the budding of enveloped viruses (HIV-1 and other lentiviruses). ESCRT-III proteins are believed to mediate the necessary vesicle extrusion and/or membrane fission activities, possibly in conjunction with the AAA ATPase VPS4. Involved in cytokinesis. Involved in recruiting VPS4A and/or VPS4B to the midbody of dividing cells. May also be involved in chromosome condensation. Targets the Polycomb group (PcG) protein BMI1/PCGF4 to regions of condensed chromatin. May play a role in stable cell cycle progression and in PcG gene silencing.^{[4] [5] [6] [7] [8]}

Evolutionary Conservation

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

See Also

• Vacuolar protein sorting-associated protein 3D structures

References

1. ↑ Scheuring S, Rohricht RA, Schoning-Burkhardt B, Beyer A, Muller S, Abts HF, Kohrer K. Mammalian cells express two VPS4 proteins both of which are involved in intracellular protein trafficking. J Mol Biol. 2001 Sep 21;312(3):469-80. PMID:11563910 doi:10.1006/jmbi.2001.4917
2. ↑ Garrus JE, von Schwedler UK, Pornillos OW, Morham SG, Zavitz KH, Wang HE, Wettstein DA, Stray KM, Cote M, Rich RL, Myszka DG, Sundquist WI. Tsg101 and the vacuolar protein sorting pathway are essential for HIV-1 budding. Cell. 2001 Oct 5;107(1):55-65. PMID:11595185
3. ↑ Sachse M, Strous GJ, Klumperman J. ATPase-deficient hVPS4 impairs formation of internal endosomal vesicles and stabilizes bilayered clathrin coats on endosomal vacuoles. J Cell Sci. 2004 Apr 1;117(Pt 9):1699-708. Epub 2004 Mar 9. PMID:15075231 doi:http://dx.doi.org/10.1242/jcs.00998
4. ↑ Scott IC, Halila R, Jenkins JM, Mehan S, Apostolou S, Winqvist R, Callen DF, Prockop DJ, Peltonen L, Kadler KE. Molecular cloning, expression and chromosomal localization of a human gene encoding a 33 kDa putative metallopeptidase (PRSM1). Gene. 1996 Sep 26;174(1):135-43. PMID:8863740
5. ↑ Stauffer DR, Howard TL, Nyun T, Hollenberg SM. CHMP1 is a novel nuclear matrix protein affecting chromatin structure and cell-cycle progression. J Cell Sci. 2001 Jul;114(Pt 13):2383-93. PMID:11559747
6. ↑ Howard TL, Stauffer DR, Degnin CR, Hollenberg SM. CHMP1 functions as a member of a newly defined family of vesicle trafficking proteins. J Cell Sci. 2001 Jul;114(Pt 13):2395-404. PMID:11559748
7. ↑ Bajorek M, Morita E, Skalicky JJ, Morham SG, Babst M, Sundquist WI. Biochemical analyses of human IST1 and its function in cytokinesis. Mol Biol Cell. 2009 Mar;20(5):1360-73. doi: 10.1091/mbc.E08-05-0475. Epub 2009, Jan 7. PMID:19129479 doi:http://dx.doi.org/10.1091/mbc.E08-05-0475
8. ↑ Hadders MA, Agromayor M, Obita T, Perisic O, Caballe A, Kloc M, Lamers MH, Williams RL, Martin-Serrano J. ESCRT-III binding protein MITD1 is involved in cytokinesis and has an unanticipated PLD fold that binds membranes. Proc Natl Acad Sci U S A. 2012 Oct 8. PMID:23045692 doi:http://dx.doi.org/10.1073/pnas.1206839109
9. ↑ Stuchell-Brereton MD, Skalicky JJ, Kieffer C, Karren MA, Ghaffarian S, Sundquist WI. ESCRT-III recognition by VPS4 ATPases. Nature. 2007 Oct 11;449(7163):740-4. PMID:17928862 doi:http://dx.doi.org/10.1038/nature06172