The anaphase inhibitor Pds1 binds to the APC/C-associated protein Cdc20 in a destruction box-dependent manner.
An essential aspect of progression through mitosis is the sequential degradation of key mitotic regulators in a process that is mediated by the anaphase promoting complex/cyclosome (APC/C) ubiquitin ligase [1]. In mitotic cells, two forms of the APC/C exist, APC/C(Cdc20) and APC/C(Cdh1), which differ in their associated WD-repeat proteins (Cdc20 and Cdh1, respectively), time of activation, and substrate specificity [2, 3]. How the WD-repeat proteins contribute to APC/C's activation and substrate specificity is not clear. Many APC/C substrates contain a destruction box element that is necessary for their ubiquitination [4-6]. One such APC/C substrate, the budding yeast anaphase inhibitor Pds1 (securin), is degraded prior to anaphase initiation in a destruction box and APC/C(Cdc20)-dependent manner [3, 7]. Here we find that Pds1 interacts directly with Cdc20 and that this interaction requires Pds1's destruction box. Our results suggest that Cdc20 provides a link between the substrate and the core APC/C and that the destruction box is essential for efficient Cdc20-substrate interaction. We also find that Pds1 does not interact with Cdh1. Finally, the effect of spindle assembly checkpoint activation, known to inhibit APC/C function [8], on the Pds1-Cdc20 interaction is examined.
Hilioti
Z
Z
The Laboratory of Molecular and Cellular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
Chung
Y S
YS
Mochizuki
Y
Y
Hardy
C F
CF
Cohen-Fix
O
O
D000705:Anaphase; D064173:Anaphase-Promoting Complex-Cyclosome; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D008025:Ligases / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D029701:Saccharomyces cerevisiae Proteins; D064249:Securin; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases
C577495:CDC20 protein, S cerevisiae; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D009687:Nuclear Proteins; C578004:PDS1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D064249:Securin; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D044767:Ubiquitin-Protein Ligases; D008025:Ligases