The AAA (ATPase associated with various cellular activities) proteins participate in membrane trafficking, organelle biogenesis, DNA replication, intracellular locomotion, cytoskeletal remodelling, protein folding and proteolysis. The AAA Vps (vacuolar protein sorting) 4 is central to traffic to lysosomes, retroviral budding and mammalian cell division. It dissociates ESCRTs (endosomal sorting complexes required for transport) from endosomal membranes, enabling their recycling to the cytosol, and plays a role in fission of intraluminal vesicles within MVBs (multivesicular bodies).
View Article and Find Full Text PDFThe ESCRT machinery mediates sorting of ubiquitinated transmembrane proteins to lysosomes via multivesicular bodies (MVBs) and also has roles in cytokinesis and viral budding. The ESCRT-III subunits are metastable monomers that transiently assemble on membranes. However, the nature of these assemblies is unknown.
View Article and Find Full Text PDFThe AAA+ ATPases are essential for various activities such as membrane trafficking, organelle biogenesis, DNA replication, intracellular locomotion, cytoskeletal remodelling, protein folding and proteolysis. The AAA ATPase Vps4, which is central to endosomal traffic to lysosomes, retroviral budding and cytokinesis, dissociates ESCRT complexes (the endosomal sorting complexes required for transport) from membranes. Here we show that, of the six ESCRT--related subunits in yeast, only Vps2 and Did2 bind the MIT (microtubule interacting and transport) domain of Vps4, and that the carboxy-terminal 30 residues of the subunits are both necessary and sufficient for interaction.
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