Biomaterial Database

ESCRT-II coordinates the assembly of ESCRT-III filaments for cargo sorting and multivesicular body vesicle formation. 2010

David Teis, and Suraj Saksena, and Bret L Judson, and Scott D Emr

Biocenter, Medical University Innsbruck, Austria. david.teis@i-med.ac.at

The sequential action of five distinct endosomal-sorting complex required for transport (ESCRT) complexes is required for the lysosomal downregulation of cell surface receptors through the multivesicular body (MVB) pathway. On endosomes, the assembly of ESCRT-III is a highly ordered process. We show that the length of ESCRT-III (Snf7) oligomers controls the size of MVB vesicles and addresses how ESCRT-II regulates ESCRT-III assembly. The first step of ESCRT-III assembly is mediated by Vps20, which nucleates Snf7/Vps32 oligomerization, and serves as the link to ESCRT-II. The ESCRT-II subunit Vps25 induces an essential conformational switch that converts inactive monomeric Vps20 into the active nucleator for Snf7 oligomerization. Each ESCRT-II complex contains two Vps25 molecules (arms) that generate a characteristic Y-shaped structure. Mutant 'one-armed' ESCRT-II complexes with a single Vps25 arm are sufficient to nucleate Snf7 oligomerization. However, these oligomers cannot execute ESCRT-III function. Both Vps25 arms provide essential geometry for the assembly of a functional ESCRT-III complex. We propose that ESCRT-II serves as a scaffold that nucleates the assembly of two Snf7 oligomers, which together are required for cargo sequestration and vesicle formation during MVB sorting.

UI	MeSH Term	Description	Entries
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D011992	Endosomes	Cytoplasmic vesicles formed when COATED VESICLES shed their CLATHRIN coat. Endosomes internalize macromolecules bound by receptors on the cell surface.	Receptosomes,Endosome,Receptosome
D002850	Chromatography, Gel	Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.	Chromatography, Exclusion,Chromatography, Gel Permeation,Chromatography, Molecular Sieve,Gel Filtration,Gel Filtration Chromatography,Chromatography, Size Exclusion,Exclusion Chromatography,Gel Chromatography,Gel Permeation Chromatography,Molecular Sieve Chromatography,Chromatography, Gel Filtration,Exclusion Chromatography, Size,Filtration Chromatography, Gel,Filtration, Gel,Sieve Chromatography, Molecular,Size Exclusion Chromatography
D012441	Saccharomyces cerevisiae	A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.	Baker's Yeast,Brewer's Yeast,Candida robusta,S. cerevisiae,Saccharomyces capensis,Saccharomyces italicus,Saccharomyces oviformis,Saccharomyces uvarum var. melibiosus,Yeast, Baker's,Yeast, Brewer's,Baker Yeast,S cerevisiae,Baker's Yeasts,Yeast, Baker
D013050	Spectrometry, Fluorescence	Measurement of the intensity and quality of fluorescence.	Fluorescence Spectrophotometry,Fluorescence Spectroscopy,Spectrofluorometry,Fluorescence Spectrometry,Spectrophotometry, Fluorescence,Spectroscopy, Fluorescence
D046529	Microscopy, Electron, Transmission	Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.	Electron Diffraction Microscopy,Electron Microscopy, Transmission,Microscopy, Electron Diffraction,Transmission Electron Microscopy,Diffraction Microscopy, Electron,Microscopy, Transmission Electron
D056827	Endosomal Sorting Complexes Required for Transport	A set of protein subcomplexes involved in PROTEIN SORTING of UBIQUITINATED PROTEINS into intraluminal vesicles of MULTIVESICULAR BODIES and in membrane scission during formation of intraluminal vesicles, during the final step of CYTOKINESIS, and during the budding of enveloped viruses. The ESCRT machinery is comprised of the protein products of Class E vacuolar protein sorting genes.	ESCRT Complexes,ESCRT I,ESCRT II,ESCRT III,ESCRT Machinery,Endosomal Sorting Complex Required for Transport,Endosomal Sorting Complex Required for Transport I,Endosomal Sorting Complex Required for Transport II,Endosomal Sorting Complex Required for Transport III,Endosomal Sorting Complex Required for Transport Machinery,Complexes, ESCRT,Machinery, ESCRT
D021381	Protein Transport	The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.	Cellular Protein Targeting,Gated Protein Transport,Protein Targeting, Cellular,Protein Translocation,Transmembrane Protein Transport,Vesicular Protein Transport,Protein Localization Processes, Cellular,Protein Sorting,Protein Trafficking,Protein Transport, Gated,Protein Transport, Transmembrane,Protein Transport, Vesicular,Traffickings, Protein
D029701	Saccharomyces cerevisiae Proteins	Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.	Baker's Yeast Proteins,S cerevisiae Proteins