5fvl
From Proteopedia
Crystal structure of Vps4-Vps20 complex from S.cerevisiae
Structural highlights
FunctionVPS20_YEAST Class E VPS protein implicated in concentration and sorting of cargo proteins of the multivesicular body (MVB) for incorporation into intralumenal vesicles. The lumenal sequestrated membrane proteins will be targeted into the vacuole after fusion of the endosome with the vacuole. Acts a component of the ESCRT-III complex, which appears to be critical for late steps in MVB sorting, such as membrane invagination and final cargo sorting and recruitment of late-acting components of the sorting machinery. The MVB pathway requires the sequential function of ESCRT-O, -I,-II and -III complex assemblies. Required for the oligomerization of SNF7 into a membrane-associated filament. The VPS20-SNF7 subcomplex is responsible for the membrane association of the ESCRT-III complex. Also required for the RIM101 repressor proteolytic activation.[1] [2] [3] [4] [5] Publication Abstract from PubMedThe endosomal sorting complex required for transport (ESCRT) facilitates roles in membrane remodeling, such as multivesicular body biogenesis, enveloped virus budding and cell division. In yeast, Vps4 plays a crucial role in intraluminal vesicle formation by disassembling ESCRT proteins. Vps4 is recruited by ESCRT-III proteins to the endosomal membrane through the interaction between the microtubule interacting and trafficking (MIT) domain of Vps4 and the C-terminal MIT-interacting motif (MIM) of ESCRT-III proteins. Here, we have determined the crystal structure of Vps4-MIT in a complex with Vps20, a member of ESCRT-III, and revealed that Vps20 adopts a unique MIM2 conformation. Based on structural comparisons with other known MIM2s, we have refined the consensus sequence of MIM2. We have shown that another ESCRT-III protein, Ist1, binds to Vps4-MIT via its C-terminal MIM1 with higher affinity than Vps2, but lacks MIM2 by surface plasmon resonance. Surprisingly, the Ist1 MIM1 competed with the MIM2 of Vfa1, a regulator of Vps4, for binding to Vps4-MIT, even though these MIMs bind in non-overlapping sites on the MIT. These findings provide insight into the allosteric recognition of MIMs of ESCRT-III by Vps4 and also the regulation of ESCRT machinery at the last step of membrane remodeling. Structural Fine-Tuning of MIT-Interacting Motif 2 (MIM2) and Allosteric Regulation of ESCRT-III by Vps4 in Yeast.,Kojima R, Obita T, Onoue K, Mizuguchi M J Mol Biol. 2016 Apr 10. pii: S0022-2836(16)30051-1. doi:, 10.1016/j.jmb.2016.04.007. PMID:27075672[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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