title: NMR-based insights into the conformational and interaction properties of Arkadia RING-H2 E3 Ub ligase.
abstract: Arkadia (Rnf111), an E3 Ubiquitin (Ub) ligase, amplifies TGF-β signaling responses by targeting for degradation of the negative regulators Smad6/7 and the SnoN/Ski transcriptional repressors when they block the TGF-β effectors Smad2/3. The E3 ligase activity of Arkadia depends on its C-terminal RING-H2 domain that constitutes the docking site for the E2 Ub-conjugating enzyme carrying the activated Ub. We determined the nuclear magnetic resonance solution structure of Arkadia's RING-H2 domain and revealed a (β)ββα fold, fully consistent with the expected "cross-brace" mode of Zn(II)-ligation. In addition, the interaction of the Arkadia RING-H2 domain with its E2 partner enzyme (UbcH5b) was examined through chemical shift perturbation. Proteins 2012. © 2012 Wiley Periodicals, Inc.
authors.affiliation: Department of Pharmacy, University of Patras, Patras GR-26504, Greece.
authors.forename: Christos T
authors.initials: CT
authors.lastname: Chasapis
authors.forename: Nikolaos G
authors.initials: NG
authors.lastname: Kandias
authors.forename: Vasso
authors.initials: V
authors.lastname: Episkopou
authors.forename: Detlef
authors.initials: D
authors.lastname: Bentrop
authors.forename: Georgios A
authors.initials: GA
authors.lastname: Spyroulias
mesh_terms: D006801:Humans; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D009687:Nuclear Proteins / Q000737:chemistry* / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation; D054730:Protein Interaction Domains and Motifs; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D009687:Nuclear Proteins; D010446:Peptide Fragments; C486067:RNF111 protein, human; D044767:Ubiquitin-Protein Ligases