title: Aurora-A overexpression reveals tetraploidization as a major route to centrosome amplification in p53-/- cells.
abstract: Aberrations in centrosome numbers have long been implicated in aneuploidy and tumorigenesis, but their origins are unknown. Here we have examined how overexpression of Aurora-A kinase causes centrosome amplification in cultured cells. We show that excess Aurora-A does not deregulate centrosome duplication but gives rise to extra centrosomes through defects in cell division and consequent tetraploidization. Over expression of other mitotic kinases (Polo-like kinase 1 and Aurora-B) also causes multinucleation and concomitant increases in centrosome numbers. Absence of a p53 checkpoint exacerbates this phenotype, providing a plausible explanation for the centrosome amplification typical of p53-/- cells. We propose that errors during cell division, combined with the inability to detect the resulting hyperploidy, constitute a major cause for numerical centrosome aberrations in tumors.
authors.affiliation: Department of Cell Biology, Max-Planck-Institute for Biochemistry, D-82152 Martinsried, Germany.
authors.forename: Patrick
authors.initials: P
authors.lastname: Meraldi
authors.forename: Reiko
authors.initials: R
authors.lastname: Honda
authors.forename: Erich A
authors.initials: EA
authors.lastname: Nigg
mesh_terms: D000818:Animals; D064096:Aurora Kinase A; D064107:Aurora Kinase B; D064127:Aurora Kinases; D002460:Cell Line; D018385:Centrosome; D006224:Cricetinae; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D051379:Mice; D011123:Polyploidy; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000502:physiology*
chemical_list: D016159:Tumor Suppressor Protein p53; C576921:AURKB protein, human; C576918:Aurka protein, mouse; C576924:Aurkb protein, mouse; D064096:Aurora Kinase A; D064107:Aurora Kinase B; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases