5uie
From Proteopedia
Vps4-Vta1 complex
Structural highlights
Function[VPS4_YEAST] Involved in the transport of biosynthetic membrane proteins from the prevacuolar/endosomal compartment to the vacuole. Required for multivesicular body (MVB) protein sorting. Catalyzes the ATP-dependent dissociation of class E VPS proteins from endosomal membranes, such as the disassembly of the ESCRT-III complex.[1] [2] [3] [VTA1_YEAST] Has a role in the formation of the multivesicular body (MVB). Required for the sorting of lipids to form intralumenal vesicles and for fluid-phase transport to the vacuole. Required for sorting the plasma membrane proteins STE2 and STE3 into the MVB. Acts a cofactor of VSP4, promotes the oligomerization of VPS4 and stimulates its ATPase activity by 6- to 8-fold.[4] [5] [6] [7] Publication Abstract from PubMedMany important cellular membrane fission reactions are driven by ESCRT pathways, which culminate in disassembly of ESCRT-III polymers by the AAA ATPase Vps4. We report a 4.3 A resolution cryo-EM structure of the active Vps4 hexamer with its cofactor Vta1, ADP.BeFx, and an ESCRT-III substrate peptide. Four Vps4 subunits form a helix whose interfaces are consistent with ATP binding, is stabilized by Vta1, and binds the substrate peptide. The fifth subunit approximately continues this helix but appears to be dissociating. The final Vps4 subunit completes a notched-washer configuration as if transitioning between the ends of the helix. We propose that ATP binding propagates growth at one end of the helix while hydrolysis promotes disassembly at the other end, so that Vps4 'walks' along ESCRT-III until it encounters the ordered N-terminal domain to destabilize the ESCRT-III lattice. This model may be generally applicable to other protein-translocating AAA ATPases. Structural basis of protein translocation by the Vps4-Vta1 AAA ATPase.,Monroe N, Han H, Shen PS, Sundquist WI, Hill CP Elife. 2017 Apr 5;6. doi: 10.7554/eLife.24487. PMID:28379137[8] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Atcc 18824 | Large Structures | Han, H | Hill, C P | Monroe, N | Shen, P | Sundquist, W I | Aaa atpase | Escrt | Transport protein | Vps4 | Vta1
