Linked Life Data

21193406

Source:http://linkedlifedata.com/resource/pubmed/id/21193406

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2011-3-30
pubmed:abstractText
The ESCRT machinery consists of multiple protein complexes that collectively participate in the biogenesis of multivesicular endosomes (MVEs). The ESCRT-0 complex is composed of two subunits, Hrs and STAM, both of which can engage ubiquitinylated substrates destined for lysosomal degradation. Here, we conduct a comprehensive analysis of ESCRT-0:ubiquitin interactions using isothermal titration calorimetry and define the affinity of each ubiquitin-binding domain (UBD) within the intact ESCRT-0 complex. Our data demonstrate that ubiquitin binding is non-cooperative between the ESCRT-0 UBDs. Additionally, our findings show that the affinity of the Hrs double ubiquitin interacting motif (DUIM) for ubiquitin is more than 2-fold greater than that of UBDs found in STAM, suggesting that Hrs functions as the major ubiquitin-binding protein in ESCRT-0. In vivo, Hrs and STAM localize to endosomal membranes. To study recombinant ESCRT-0 assembly on lipid bilayers, we used atomic force microscopy. Our data show that ESCRT-0 forms mostly heterodimers and heterotetramers of Hrs and STAM when analyzed in the presence of membranes. Consistent with these findings, hydrodynamic analysis of endogenous ESCRT-0 indicates that it exists largely as a heterotetrameric complex of its two subunits. Based on these data, we present a revised model for ESCRT-0 function in cargo recruitment and concentration at the endosome.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1083-351X
pubmed:author
pubmed:issnType
Electronic
pubmed:day
18
pubmed:volume
286
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9636-45
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
ESCRT-0 assembles as a heterotetrameric complex on membranes and binds multiple ubiquitinylated cargoes simultaneously.
pubmed:affiliation
Department of Biomolecular Chemistry, University of Wisconsin-Madison Medical School, Madison, Wisconsin 53706, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural