A functional interplay between Aurora-A, Plk1 and TPX2 at spindle poles: Plk1 controls centrosomal localization of Aurora-A and TPX2 spindle association.
Aurora-A and Plk1 are centrosomal kinases involved in centrosome maturation and spindle assembly. The microtubule-binding protein TPX2 interacts with, and activates, Aurora-A. Here we have used RNA interference-mediated inactivation to investigate whether Aurora-A, Plk1 and TPX2 act independently or are part of one signaling cascade in spindle formation in mammalian cells. We have identified both specific, and over- lapping, roles of each single regulator in centrosome maturation and spindle formation: (1) Aurora-A and TPX2 are required for centriole cohesion and spindle bipolarity; (2) TPX2, besides its known role in microtubule organization, is also involved in centrosome maturation; (3) finally, Plk1 controls the localization of Aurora-A to centrosomes, as well as TPX2 recruitment to microtubules. Based on these results therefore a hierarchical functional relation between Plk1 and the Aurora-A/TPX2 pathway emerges.
De Luca
Maria
M
Institute of Molecular Biology and Pathology, CNR, University of Rome La Sapienza, Rome, Italy.
Lavia
Patrizia
P
Guarguaglini
Giulia
G
D064127:Aurora Kinases; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D008938:Mitosis / Q000502:physiology*; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D015398:Signal Transduction; D008941:Spindle Apparatus / Q000378:metabolism* / Q000648:ultrastructure; D000097869:Polo-Like Kinase 1
D064127:Aurora Kinases; D018797:Cell Cycle Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D000097869:Polo-Like Kinase 1; C122167:TPX2 protein, human