4u7e

Structural highlights

Function

[VTA1_HUMAN] Involved in the endosomal multivesicular bodies (MVB) pathway. 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. Thought to be a cofactor of VPS4A/B, which catalyzes disassembles membrane-associated ESCRT-III assemblies. Involved in the sorting and down-regulation of EGFR (By similarity). Involved in HIV-1 budding.^[1] [IST1_HUMAN] Proposed to be involved in specific functions of the ESCRT machinery. Is required for efficient abscission during cytokinesis, but not for HIV-1 budding. The involvement in the MVB pathway is not established. Involved in recruiting VPS4A and/or VPS4B to the midbody of dividing cells.^{[2] [3]}

References

1. ↑ Ward DM, Vaughn MB, Shiflett SL, White PL, Pollock AL, Hill J, Schnegelberger R, Sundquist WI, Kaplan J. The role of LIP5 and CHMP5 in multivesicular body formation and HIV-1 budding in mammalian cells. J Biol Chem. 2005 Mar 18;280(11):10548-55. Epub 2005 Jan 11. PMID:15644320 doi:http://dx.doi.org/M413734200
2. ↑ 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
3. ↑ Agromayor M, Carlton JG, Phelan JP, Matthews DR, Carlin LM, Ameer-Beg S, Bowers K, Martin-Serrano J. Essential role of hIST1 in cytokinesis. Mol Biol Cell. 2009 Mar;20(5):1374-87. doi: 10.1091/mbc.E08-05-0474. Epub 2009, Jan 7. PMID:19129480 doi:http://dx.doi.org/10.1091/mbc.E08-05-0474