Charged multivesicular body protein 1b (CHMP1B)

Probable peripherally associated component of the endosomal sorting needed for transport complex III (ESCRT-III) that is involved in multivesicular bodies (MVBs) formation and sorting of endosomal cargo proteins into MVBs. MVBs include intraluminal vesicles (ILVs) which are generated by invagination and scission from the limiting membrane of the endosome and are usually delivered to lysosomes enabling degradation of membrane proteins, such as stimulated growth factor receptors, lysosomal enzymes and lipids.

The MVB pathway seems to require the sequential use of ESCRT-O, -I,-II and -III complexes. ESCRT- III proteins mostly dissociate from the invaginating membrane until the ILV is released.