title: Structural Analysis of a Complex between Small Ubiquitin-like Modifier 1 (SUMO1) and the ZZ Domain of CREB-binding Protein (CBP/p300) Reveals a New Interaction Surface on SUMO.
abstract: We have recently discovered that the ZZ zinc finger domain represents a novel small ubiquitin-like modifier (SUMO) binding motif. In this study we identify the binding epitopes in the ZZ domain of CBP (CREB-binding protein) and SUMO1 using NMR spectroscopy. The binding site on SUMO1 represents a unique epitope for SUMO interaction spatially opposite to that observed for canonical SUMO interaction motifs (SIMs). HADDOCK docking simulations using chemical shift perturbations and residual dipolar couplings was employed to obtain a structural model for the ZZ domain-SUMO1 complex. Isothermal titration calorimetry experiments support this model by showing that the mutation of key residues in the binding site abolishes binding and that SUMO1 can simultaneously and non-cooperatively bind both the ZZ domain and a canonical SIM motif. The binding dynamics of SUMO1 was further characterized using (15)N Carr-Purcell-Meiboom-Gill (CPMG) relaxation dispersions, which define the off rates for the ZZ domain and SIM motif and show that the dynamic binding process has different characteristics for the two cases. Furthermore, in the absence of bound ligands SUMO1 transiently samples a high energy conformation, which might be involved in ligand binding.
authors.affiliation: From the Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark,; SARomics Biostructures, SE-22363 Lund, Sweden.
authors.forename: Carl
authors.initials: C
authors.lastname: Diehl
authors.affiliation: Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, SE-22100 Lund, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Akke
authors.affiliation: From the Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark.
authors.forename: Simon
authors.initials: S
authors.lastname: Bekker-Jensen
authors.affiliation: From the Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark.
authors.forename: Niels
authors.initials: N
authors.lastname: Mailand
authors.affiliation: From the Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark,; Novozymes A/S, DK-2880 Bagsvaerd, Denmark, and.
authors.forename: Werner
authors.initials: W
authors.lastname: Streicher
authors.affiliation: From the Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark,; Amgen Inc., Thousand Oaks, California 91320. Electronic address: mats.wikstrom@amgen.com.
authors.forename: Mats
authors.initials: M
authors.lastname: Wikström
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001665:Binding Sites / Q000235:genetics; D050882:CREB-Binding Protein / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D002151:Calorimetry / Q000379:methods; D000939:Epitopes / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009154:Mutation; D011485:Protein Binding; D000072417:Protein Domains; D025842:SUMO-1 Protein / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D013816:Thermodynamics
chemical_list: D000939:Epitopes; D008024:Ligands; D025842:SUMO-1 Protein; C495501:SUMO1 protein, human; D050882:CREB-Binding Protein; C494363:CREBBP protein, human
keywords: SUMO-interacting motif (SIM); biophysics; nuclear magnetic resonance (NMR); protein dynamics; protein structure; protein-protein interaction; structural biology; structural model