1gqp
From Proteopedia
APC10/DOC1 SUBUNIT OF S. cerevisiae
Structural highlights
FunctionAPC10_YEAST Component of the anaphase promoting complex/cyclosome (APC/C), a cell cycle-regulated E3 ubiquitin-protein ligase complex that controls progression through mitosis and the G1 phase of the cell cycle. The APC/C is thought to confer substrate specificity and, in the presence of ubiquitin-conjugating E2 enzymes, it catalyzes the formation of protein-ubiquitin conjugates that are subsequently degraded by the 26S proteasome. In early mitosis, the APC/C is activated by CDC20 and targets securin PDS1, the B-type cyclin CLB5, and other anaphase inhibitory proteins for proteolysis, thereby triggering the separation of sister chromatids at the metaphase-to-anaphase transition. In late mitosis and in G1, degradation of CLB5 allows activation of the APC/C by CDH1, which is needed to destroy CDC20 and the B-type cyclin CLB2 to allow exit from mitosis and creating the low CDK state necessary for cytokinesis and for reforming prereplicative complexes in G1 prior to another round of replication. DOC1 is required, together with the coactivators CDH1 and CDC20, for recognition and binding of the substrates.[1] [2] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe anaphase-promoting complex (APC) is a multi-subunit E3 protein ubiquitin ligase that is responsible for the metaphase to anaphase transition and the exit from mitosis. One of the subunits of the APC that is required for its ubiquitination activity is Doc1/Apc10, a protein composed of a Doc1 homology domain that has been identified in a number of diverse putative E3 ubiquitin ligases. Here, we present the crystal structure of Saccharomyces cerevisiae Doc1/Apc10 at 2.2A resolution. The Doc1 homology domain forms a beta-sandwich structure that is related in architecture to the galactose-binding domain of galactose oxidase, the coagulation factor C2 domain and a domain of XRCC1. Residues that are invariant amongst Doc1/Apc10 sequences, including a temperature-sensitive mitotic arrest mutant, map to a beta-sheet region of the molecule, whose counterpart in galactose oxidase, the coagulation factor C2 domains and XRCC1, mediate bio-molecular interactions. This finding suggests the identification of the functionally important and conserved region of Doc1/Apc10 and, since invariant residues of Doc1/Apc10 colocalise with conserved residues of other Doc1 homology domains, we propose that the Doc1 homology domains perform common ubiquitination functions in the APC and other E3 ubiquitin ligases. Implications for the ubiquitination reaction of the anaphase-promoting complex from the crystal structure of the Doc1/Apc10 subunit.,Au SW, Leng X, Harper JW, Barford D J Mol Biol. 2002 Mar 1;316(4):955-68. PMID:11884135[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||
