VPS25

Vacuolar protein-sorting-associated protein 25 is a is_associated_with::protein that in humans is encoded by the VPS25 is_associated_with::gene.

It is a component of the endosome-associated complex is_associated_with::ESCRT-II (is_associated_with::Endosomal Sorting Complexes Required for Transport protein II). ESCRT (ESCRT-I, -II, -III) complexes orchestrate efficient sorting of is_associated_with::ubiquitinated is_associated_with::transmembrane receptors to is_associated_with::lysosomes via is_associated_with::multivesicular bodies (MVBs). ESCRT-II recruits the transport machinery for protein sorting at MVB. In addition, the human ESCRT-II has been shown to form a complex with is_associated_with::RNA polymerase II elongation factor ELL in order to exert transcriptional control activity. ESCRT-II transiently associates with the is_associated_with::endosomal membrane and thereby initiates the formation of ESCRT-III, a membrane-associated is_associated_with::protein complex that functions immediately downstream of ESCRT-II during sorting of MVB cargo. ESCRT-II in turn functions downstream of ESCRT-I, a protein complex that binds to ubiquitinated endosomal cargo.

ESCRT-II is a trilobal complex composed of two copies of vps25, one copy of vps22 and the C-terminal region of vps36. The is_associated_with::crystal structure of vps25 revealed two winged-helix domains, the N-terminal domain of vps25 interacting with vps22 and vps36.