title: Crystal structure of the APC10/DOC1 subunit of the human anaphase-promoting complex.
abstract: The anaphase-promoting complex (APC), or cyclosome, is a cell cycle-regulated ubiquitin ligase that controls progression through mitosis and the G1 phase of the cell cycle. The APC is composed of at least 11 subunits; no structure has been determined for any of these subunits. The subunit APC10/DOC1, a one-domain protein consisting of 185 amino acids, has a conserved core (residues 22-161) that is homologous to domains found in several other putative ubiquitin ligases and, therefore, may play a role in ubiquitination reactions. Here we report the crystal structure of human APC10 at 1.6 A resolution. The core of the protein is formed by a beta-sandwich that adopts a jellyroll fold. Unexpectedly, this structure is highly similar to ligand-binding domains of several bacterial and eukaryotic proteins, such as galactose oxidase and coagulation factor Va, raising the possibility that APC10 may function by binding a yet unidentified ligand. We further provide biochemical evidence that the C-terminus of APC10 binds to CDC27/APC3, an APC subunit that contains multiple tetratrico peptide repeats.
authors.affiliation: Max-Planck-Institut für Biochemie, Abteilung Strukturforschung, Am Klopferspitz 18a, D-82152 Martinsried, Germany. wendt@biochem.mpg.de
authors.forename: K S
authors.initials: KS
authors.lastname: Wendt
authors.forename: H C
authors.initials: HC
authors.lastname: Vodermaier
authors.forename: U
authors.initials: U
authors.lastname: Jacob
authors.forename: C
authors.initials: C
authors.lastname: Gieffers
authors.forename: M
authors.initials: M
authors.lastname: Gmachl
authors.forename: J M
authors.initials: JM
authors.lastname: Peters
authors.forename: R
authors.initials: R
authors.lastname: Huber
authors.forename: P
authors.initials: P
authors.lastname: Sondermann
mesh_terms: D000595:Amino Acid Sequence; D064173:Anaphase-Promoting Complex-Cyclosome; D064191:Apc3 Subunit, Anaphase-Promoting Complex-Cyclosome; D018797:Cell Cycle Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D018360:Crystallography, X-Ray; D006801:Humans; D008025:Ligases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011233:Precipitin Tests; D011485:Protein Binding; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D021122:Protein Subunits; D016415:Sequence Alignment; D055672:Static Electricity; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases
chemical_list: D064191:Apc3 Subunit, Anaphase-Promoting Complex-Cyclosome; C577366:CDC27 protein, human; D018797:Cell Cycle Proteins; D021122:Protein Subunits; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D044767:Ubiquitin-Protein Ligases; D008025:Ligases