An essential function of the C. elegans ortholog of TPX2 is to localize activated aurora A kinase to mitotic spindles.
In vertebrates, the microtubule binding protein TPX2 is required for meiotic and mitotic spindle assembly. TPX2 is also known to bind to and activate Aurora A kinase and target it to the spindle. However, the relationship between the TPX2-Aurora A interaction and the role of TPX2 in spindle assembly is unclear. Here, we identify TPXL-1, a C. elegans protein that is the first characterized invertebrate ortholog of TPX2. We demonstrate that an essential role of TPXL-1 during mitosis is to activate and target Aurora A to microtubules. Our data suggest that this targeting stabilizes microtubules connecting kinetochores to the spindle poles. Thus, activation and targeting of Aurora A appears to be an ancient and conserved function of TPX2 that plays a central role in mitotic spindle assembly.
Ozlü
Nurhan
N
Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, Dresden 01307, Germany. ozlu@mpi-cbg.de
Srayko
Martin
M
Kinoshita
Kazuhisa
K
Habermann
Bianca
B
O'toole
Eileen T
ET
Müller-Reichert
Thomas
T
Schmalz
Natalie
N
Desai
Arshad
A
Hyman
Anthony A
AA
D000595:Amino Acid Sequence; D000818:Animals; D064127:Aurora Kinases; D017173:Caenorhabditis elegans / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000502:physiology*; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D004625:Embryo, Nonmammalian / Q000502:physiology; D004789:Enzyme Activation; D006801:Humans; D018386:Kinetochores / Q000502:physiology; D008869:Microtubule-Associated Proteins / Q000235:genetics; D008870:Microtubules / Q000502:physiology*; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics; D010750:Phosphoproteins / Q000235:genetics; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases; D017386:Sequence Homology, Amino Acid; D008941:Spindle Apparatus / Q000235:genetics / Q000502:physiology*; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*
D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; C122167:TPX2 protein, human; C504801:TPXL-1 protein, C elegans; D029867:Xenopus Proteins; D011494:Protein Kinases; C112134:AURKA protein, Xenopus; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases