Format

Send to:

Choose Destination
See comment in PubMed Commons below
Science. 2009 Mar 13;323(5920):1477-81. doi: 10.1126/science.1163300.

Structure of the anaphase-promoting complex/cyclosome interacting with a mitotic checkpoint complex.

Author information

  • 1Research Institute of Molecular Pathology, Dr. Bohr-Gasse 7, 1030 Vienna, Austria.

Abstract

Once all chromosomes are connected to the mitotic spindle (bioriented), anaphase is initiated by the protein ubiquitylation activity of the anaphase-promoting complex/cyclosome (APC/C) and its coactivator Cdc20 (APC/C(Cdc20)). Before chromosome biorientation, anaphase is delayed by a mitotic checkpoint complex (MCC) that inhibits APC/C(Cdc20). We used single-particle electron microscopy to obtain three-dimensional models of human APC/C in various functional states: bound to MCC, to Cdc20, or to neither (apo-APC/C). These experiments revealed that MCC associates with the Cdc20 binding site on APC/C, locks the otherwise flexible APC/C in a "closed" state, and prevents binding and ubiquitylation of a wide range of different APC/C substrates. These observations clarify the structural basis for the inhibition of APC/C by spindle checkpoint proteins.

PMID:
19286556
[PubMed - indexed for MEDLINE]
PMCID:
PMC2989460
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk