APC/Fizzy-Related targets Aurora-A kinase for proteolysis.
Aurora-A kinase is a mitotic spindle-pole-associated protein that has been implicated in duplication and separation of centrosomes and in spindle assembly. The proper timing and amplitude of Aurora-A expression seems to be important, as elevated levels of this protein have been associated with centrosome abnormalities and aneuploidy in mammalian cells. We show that Aurora-A increases at the G2-M transistion and disappears completely at G1 in XL2 cells. Using Xenopus oocyte extracts, we demonstrate that degradation of Aurora-A is mediated by the anaphase-promoting complex (APC) and is regulated by Fizzy-Related but not by Fizzy. Degradation of Aurora-A depends on a D-Box, but not on its KEN-Box motif, as mutation of its C-terminal D-Box sequence induces stabilization of the protein. Accordingly, addition into the extracts of a cyclin B-type D-Box-motif-containing peptide completely suppresses its degradation. Furthermore, APC/Fizzy-Related ubiquitylates the wild type but not a D-Box mutant form of Aurora-A in vitro. Consistent with these data, ectopic expression of Fizzy-Related in Xenopus oocytes induces complete degradation of endogenous Aurora-A. Aurora-A is thus the first protein, at least in our assay system, that undergoes a D-Box-dependent degradation mediated by APC/Fizzy-Related but not by APC/Fizzy.
Castro
Anna
A
Centre de Recherche de Biochimie Macromoléculaire, CNRS UPR 1086, 1919 Route de Mende, F-34293 Montpellier Cedex 5, France.
Arlot-Bonnemains
Yannick
Y
Vigneron
Suzanne
S
Labbé
Jean-Claude
JC
Prigent
Claude
C
Lorca
Thierry
T
D020816:Amino Acid Motifs; D064173:Anaphase-Promoting Complex-Cyclosome; D000818:Animals; D064127:Aurora Kinases; D064200:Cdh1 Proteins; D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000378:metabolism*; D004926:Escherichia coli; D008025:Ligases / Q000378:metabolism; D046911:Macromolecular Substances; D009154:Mutation; D009865:Oocytes; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D043743:Ubiquitin-Protein Ligase Complexes; D014981:Xenopus; D029867:Xenopus Proteins
D064200:Cdh1 Proteins; D018797:Cell Cycle Proteins; D046911:Macromolecular Substances; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D029867:Xenopus Proteins; C577588:fzr1 protein, Xenopus; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D011494:Protein Kinases; C112134:AURKA protein, Xenopus; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases; D008025:Ligases