title: Transferring substrates to the 26S proteasome.
abstract: Ubiquitin-dependent protein degradation is not only involved in the recycling of amino acids from damaged or misfolded proteins but also represents an essential and deftly controlled mechanism for modulating the levels of key regulatory proteins. Chains of ubiquitin conjugated to a substrate protein specifically target it for degradation by the 26S proteasome, a huge multi-subunit protein complex found in all eukaryotic cells. Recent reports have clarified some of the molecular mechanisms involved in the transfer of ubiquitinated substrates from the ubiquitination machinery to the proteasome. This novel substrate transportation step in the ubiquitin-proteasome pathway seems to occur either directly or indirectly via certain substrate-recruiting proteins and appears to involve chaperones.
authors.affiliation: August Krogh Institute, University of Copenhagen, Universitetsparken 13, DK-2100 O, Copenhagen, Denmark.
authors.forename: Rasmus
authors.initials: R
authors.lastname: Hartmann-Petersen
authors.forename: Michael
authors.initials: M
authors.lastname: Seeger
authors.forename: Colin
authors.initials: C
authors.lastname: Gordon
mesh_terms: D003546:Cysteine Endopeptidases / Q000378:metabolism*; D018832:Molecular Chaperones / Q000378:metabolism; D009097:Multienzyme Complexes / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex; D013379:Substrate Specificity; D025801:Ubiquitin / Q000378:metabolism
chemical_list: D018832:Molecular Chaperones; D009097:Multienzyme Complexes; D025801:Ubiquitin; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex