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2p22
From Proteopedia
Structure of the Yeast ESCRT-I Heterotetramer Core
Overview
The endosomal sorting complex required for transport-I (ESCRT-I) complex, which is conserved from yeast to humans, directs the lysosomal degradation of ubiquitinated transmembrane proteins and the budding of the HIV virus. Yeast ESCRT-I contains four subunits, Vps23, Vps28, Vps37, and Mvb12. The crystal structure of the heterotetrameric ESCRT-I complex reveals a highly asymmetric complex of 1:1:1:1 subunit stoichiometry. The core complex is nearly 18 nm long and consists of a headpiece attached to a 13 nm stalk. The stalk is important for cargo sorting by ESCRT-I and is proposed to serve as a spacer regulating the correct disposition of cargo and other ESCRT components. Hydrodynamic constraints and crystallographic structures were used to generate a model of intact ESCRT-I in solution. The results show how ESCRT-I uses a combination of a rigid stalk and flexible tethers to interact with lipids, cargo, and other ESCRT complexes over a span of approximately 25 nm.
About this Structure
2P22 is a Protein complex structure of sequences from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Molecular architecture and functional model of the complete yeast ESCRT-I heterotetramer., Kostelansky MS, Schluter C, Tam YY, Lee S, Ghirlando R, Beach B, Conibear E, Hurley JH, Cell. 2007 May 4;129(3):485-98. Epub 2007 Apr 19. PMID:17442384 Page seeded by OCA on Sun May 4 12:10:32 2008
