Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
26
pubmed:dateCreated
2004-6-21
pubmed:abstractText
The selective recognition of ubiquitin conjugates by proteasomes is a key step in protein degradation. The receptors that mediate this step have yet to be clearly defined although specific candidates exist. Here we show that the proteasome directly recognizes ubiquitin chains through a specific subunit, Rpn10, and also recognizes chains indirectly through Rad23, a reversibly bound proteasome cofactor. Both binding events can be observed in purified biochemical systems. A block substitution in the chain-binding ubiquitin interacting motif of RPN10 when combined with a null mutation in RAD23 results in a synthetic defect in protein degradation consistent with the view that the direct and indirect recognition modes function to some extent redundantly in vivo. Rad23 and the deubiquitinating enzyme Ubp6 both bind proteasome subunit Rpn1 through N-terminal ubiquitin-like domains. Surprisingly, Rad23 and Ubp6 do not compete with each other for proteasome binding. Thus, Rpn1 may act as a scaffold to assemble on the proteasome multiple proteins that act to either bind or hydrolyze multiubiquitin chains.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Canavanine, http://linkedlifedata.com/resource/pubmed/chemical/Carrier Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Cysteine Endopeptidases, http://linkedlifedata.com/resource/pubmed/chemical/DNA-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Endopeptidases, http://linkedlifedata.com/resource/pubmed/chemical/Fungal Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Multienzyme Complexes, http://linkedlifedata.com/resource/pubmed/chemical/Proteasome Endopeptidase Complex, http://linkedlifedata.com/resource/pubmed/chemical/Protein Subunits, http://linkedlifedata.com/resource/pubmed/chemical/RAD23 protein, S cerevisiae, http://linkedlifedata.com/resource/pubmed/chemical/RPN10 protein, S cerevisiae, http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Saccharomyces cerevisiae Proteins, http://linkedlifedata.com/resource/pubmed/chemical/UBP6 protein, S cerevisiae, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquitins
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
26817-22
pubmed:dateRevised
2009-7-24
pubmed:meshHeading
pubmed-meshheading:15117949-Amino Acid Motifs, pubmed-meshheading:15117949-Binding, Competitive, pubmed-meshheading:15117949-Canavanine, pubmed-meshheading:15117949-Carrier Proteins, pubmed-meshheading:15117949-Cysteine Endopeptidases, pubmed-meshheading:15117949-DNA-Binding Proteins, pubmed-meshheading:15117949-Endopeptidases, pubmed-meshheading:15117949-Fungal Proteins, pubmed-meshheading:15117949-Multienzyme Complexes, pubmed-meshheading:15117949-Mutation, pubmed-meshheading:15117949-Proteasome Endopeptidase Complex, pubmed-meshheading:15117949-Protein Binding, pubmed-meshheading:15117949-Protein Structure, Tertiary, pubmed-meshheading:15117949-Protein Subunits, pubmed-meshheading:15117949-Recombinant Proteins, pubmed-meshheading:15117949-Saccharomyces cerevisiae, pubmed-meshheading:15117949-Saccharomyces cerevisiae Proteins, pubmed-meshheading:15117949-Ubiquitins
pubmed:year
2004
pubmed:articleTitle
Rad23 and Rpn10 serve as alternative ubiquitin receptors for the proteasome.
pubmed:affiliation
Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't