title: The structure of the CYLD USP domain explains its specificity for Lys63-linked polyubiquitin and reveals a B box module.
abstract: The tumor suppressor CYLD antagonizes NF-kappaB and JNK signaling by disassembly of Lys63-linked ubiquitin chains synthesized in response to cytokine stimulation. Here we describe the crystal structure of the CYLD USP domain, revealing a distinctive architecture that provides molecular insights into its specificity toward Lys63-linked polyubiquitin. We identify regions of the USP domain responsible for this specificity and demonstrate endodeubiquitinase activity toward such chains. Pathogenic truncations of the CYLD C terminus, associated with the hypertrophic skin tumor cylindromatosis, disrupt the USP domain, accounting for loss of CYLD catalytic activity. A small zinc-binding B box domain, similar in structure to other crossbrace Zn-binding folds--including the RING domain found in E3 ubiquitin ligases--is inserted within the globular core of the USP domain. Biochemical and functional characterization of the B box suggests a role as a protein-interaction module that contributes to determining the subcellular localization of CYLD.
authors.affiliation: Section of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK.
authors.forename: David
authors.initials: D
authors.lastname: Komander
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Lord
authors.forename: Hartmut
authors.initials: H
authors.lastname: Scheel
authors.forename: Sally
authors.initials: S
authors.lastname: Swift
authors.forename: Kay
authors.initials: K
authors.lastname: Hofmann
authors.forename: Alan
authors.initials: A
authors.lastname: Ashworth
authors.forename: David
authors.initials: D
authors.lastname: Barford
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002460:Cell Line; D018360:Crystallography, X-Ray; D000074749:Deubiquitinating Enzyme CYLD; D016147:Genes, Tumor Suppressor; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D008239:Lysine / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D016328:NF-kappa B / Q000378:metabolism; D009369:Neoplasms / Q000235:genetics; D025821:Polyubiquitin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D015398:Signal Transduction / Q000502:physiology; D013379:Substrate Specificity; D025521:Tumor Suppressor Proteins / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D043222:Ubiquitin Thiolesterase / Q000737:chemistry / Q000235:genetics; D000076084:Ubiquitin-Specific Peptidase 7; D015032:Zinc / Q000378:metabolism
chemical_list: D016328:NF-kappa B; D011993:Recombinant Fusion Proteins; D025521:Tumor Suppressor Proteins; D025821:Polyubiquitin; D048031:JNK Mitogen-Activated Protein Kinases; C409984:CYLD protein, human; D000074749:Deubiquitinating Enzyme CYLD; C464569:USP7 protein, human; D043222:Ubiquitin Thiolesterase; D000076084:Ubiquitin-Specific Peptidase 7; D015032:Zinc; D008239:Lysine