Search Organism: All OrganismsArabidopsis thalianaBacillus subtilis 168Bos taurusCaenorhabditis elegansCanis familiarisDanio rerioDrosophila melanogasterEquus caballusEscherichia coli K12Gallus gallusHomo sapiensMacaca mulattaMus musculusNematostella vectensisOryza sativaPan troglodytesRattus norvegicusSaccharomyces cerevisiaeSchizosaccharomyces pombeStrongylocentrotus purpuratusTakifugu rubripesXenopus laevis home help / support contribute downloads mirrors about us Proc. Natl. Acad. Sci. U.S.A. Oct (2007); 104(40):15599-606 Inaugural Article- Structure and function of the yeast U-box-containing ubiquitin ligase Ufd2p- Tu D, Li W, Ye Y, Brunger AT Department of Molecular and Cellular Physiology, Stanford University and Howard Hughes Medical Institute, Stanford, CA 94305, USA- Abstract: Proteins conjugated by Lys-48-linked polyubiquitin chains are preferred substrates of the eukaryotic proteasome- Polyubiquitination requires an activating enzyme -E1-, a conjugating enzyme -E2-, and a ligase -E3-- Occasionally, these enzymes only assemble short ubiquitin oligomers, and their extension to full length involves a ubiquitin elongating factor termed E4- Ufd2p, as the first E4 identified to date, is involved in the degradation of misfolded proteins of the endoplasmic reticulum and of a ubiquitin-beta-GAL fusion substrate in Saccharomyces cerevisiae- The mechanism of action of Ufd2p is unknown- Here we describe the crystal structure of the full-length yeast Ufd2p protein- Ufd2p has an elongated shape consisting of several irregular Armadillo-like repeats with two helical hairpins protruding from it and a U-box domain flexibly attached to its C terminus- The U-box of Ufd2p has a fold similar to that of the RING -Really Interesting New Gene- domain that is present in certain ubiquitin ligases- Accordingly, Ufd2p has all of the hallmarks of a RING finger-containing ubiquitin ligase- it associates with its cognate E2 Ubc4p via its U-box domain and catalyzes the transfer of ubiquitin from the E2 active site to Ufd2p itself or to an acceptor ubiquitin molecule to form unanchored diubiquitin oligomers- Thus, Ufd2p can function as a bona fide E3 ubiquitin ligase to promote ubiquitin chain elongation on a substrate- [PUBMED: 17890322] Copyright © 2009, Tyers Lab, The Samuel Lunenfeld Research Institute, Mount Sinai Hospital, All Rights Reserved. terms and conditions - privacy policy - Osprey Network Visualization System BioGRID: A General Repository for Interaction Datasets. Chris Stark, Bobby-Joe Breitkreutz, Teresa Reguly, Lorrie Boucher, Ashton Breitkreutz, Mike Tyers. Nucleic Acids Res. Jan 1;34:D535-9.