title: Crystal structure of the N-terminal domain of anaphase-promoting complex subunit 7.
abstract: Anaphase-promoting complex or cyclosome (APC/C) is an unusual E3 ubiquitin ligase and an essential protein that controls mitotic progression. APC/C includes at least 13 subunits, but no structure has been determined for any tetratricopeptide repeat (TPR)-containing subunit (Apc3 and -6-8) in the TPR subcomplex of APC/C. Apc7 is a TPR-containing subunit that exists only in vertebrate APC/C. Here we report the crystal structure of quad mutant of nApc7 (N-terminal fragment, residues 1-147) of human Apc7 at a resolution of 2.5 A. The structure of nApc7 adopts a TPR-like motif and has a unique dimerization interface, although the protein does not contain the conserved TPR sequence. Based on the structure of nApc7, in addition to previous experimental findings, we proposed a putative homodimeric structure for full-length Apc7. This model suggests that TPR-containing subunits self-associate and bind to adaptors and substrates via an IR peptide in TPR-containing subunits of APC/C.
authors.affiliation: Department of Biomedical Sciences and Cancer Research Institute, Seoul National University College of Medicine, 28 Yongon-Dong, Seoul 110-799, Korea.
authors.forename: Dohyun
authors.initials: D
authors.lastname: Han
authors.forename: Kyunggon
authors.initials: K
authors.lastname: Kim
authors.forename: Yeonjung
authors.initials: Y
authors.lastname: Kim
authors.forename: Yup
authors.initials: Y
authors.lastname: Kang
authors.forename: Ji Yoon
authors.initials: JY
authors.lastname: Lee
authors.forename: Youngsoo
authors.initials: Y
authors.lastname: Kim
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D064173:Anaphase-Promoting Complex-Cyclosome; D064195:Apc7 Subunit, Anaphase-Promoting Complex-Cyclosome; D018360:Crystallography, X-Ray; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D018583:Pliability; D055503:Protein Multimerization; D017434:Protein Structure, Tertiary; D021122:Protein Subunits / Q000737:chemistry; D020449:Repetitive Sequences, Amino Acid; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D043743:Ubiquitin-Protein Ligase Complexes / Q000737:chemistry*
chemical_list: C577399:ANAPC7 protein, human; D064195:Apc7 Subunit, Anaphase-Promoting Complex-Cyclosome; D010446:Peptide Fragments; D021122:Protein Subunits; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome