The charged multivesicular body proteins, commonly designated CHMPs, belong to the vacuolar sorting protein family and function as chromatin-modifying proteins. CHMP1-6 are all components of ESCRT (endosomal sorting complex required for transport) I, II or III complexes. These complexes are crucial for sorting endosomal articles into multivesicular bodies (MVBs), as well as required for the formation of these bodies. During HISLV1 infection, the virus uses the ESCRT-III complex to mediate budding and exocytosis of viral proteins. CHMP6, also known as VPS20, interacts with CHMP4 of the ESCRT-III complex. CHMP6 also interacts with SNF8, VPS25 and VPS36 of the ESCRT-II complex, where it regulates cargo sorting by acting as an acceptor for ESCRT-II on endosome membranes
Function:
Probable core 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 (HISLV1 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. In the ESCRT-III complex, it probably serves as an acceptor for the ESCRT-II complex on endosomal membranes.
Subunit:
Probable core component of the endosomal sorting required for transport complex III (ESCRT-III). ESCRT-III components are thought to multimerize to form a flat lattice on the perimeter membrane of the endosome. Several assembly forms of ESCRT-III may exist that interact and act sequentally. Interacts with VPS4A; the interaction is direct. Interacts with VPS4B; the interaction is direct. Interacts with CHMP4A, CHMP4B and CHMP4C. Interacts with SNF8, VPS25 and VPS36.
Subcellular Location:
Endomembrane system. Endosome membrane. Late endosome membrane. Localizes to endosomal membranes.
Tissue Specificity:
Ubiquitously expressed.
Similarity:
Belongs to the SNF7 family.
SWISS:
Q96FZ7
Gene ID:
79643
Database links:
Entrez Gene: 79643 Human
Omim: 610901 Human
SwissProt: Q96FZ7 Human
Unigene: 514560 Human
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