title: TACC3 Is Important for Correct Progression of Meiosis in Bovine Oocytes.
abstract: Transforming acidic coiled-coil (TACC) proteins are key players during mitosis via stabilization of the spindle. The roles of TACCs during meiosis are however less clear. We used bovine oocytes to study the expression and function of TACC3 during meiosis. TACC3 mRNA was detected in bovine oocytes during meiosis using qRT-PCR, and while it was also expressed in cleavage stage embryos, its expression was down-regulated at the morula and blastocyst stages. Immunofluorescence was used to demonstrate that TACC3 co-localized with tubulin in the metaphase I and II spindles. However, TACC3 was not detected at anaphase or telophase of the first meiotic division. Aurora A, which is known to phosphorylate and activate TACC3 in mitotic cells, showed a similar pattern of gene expression to that of TACC3 in meiotic oocytes and preimplantation embryos. Aurora A protein was however only very transiently associated to the meiotic spindle. Pharmaceutical inhibition of Aurora A activity inhibited TACC3 phosphorylation but did not prevent TACC3 appearance in the spindle. Inhibiting Aurora A activity did however lead to abnormal meiotic spindle formation and impaired maturation of bovine oocytes. Similar results were obtained by knock-down of TACC3 expression using siRNA injection. These results suggest that TACC3 is important for stabilizing the meiotic spindle, but phosphorylation of TACC3 by Aurora A is not required for its recruitment to the meiotic spindle although phosphorylation of TACC3 by other kinases cannot be excluded.
authors.affiliation: Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM, Utrecht, The Netherlands.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Mahdipour
authors.affiliation: Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM, Utrecht, The Netherlands; Centro de Biologia Ambiental e Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.
authors.forename: Ana Rita Canhoto
authors.initials: AR
authors.lastname: Leitoguinho
authors.affiliation: Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM, Utrecht, The Netherlands; Centro de Biologia Ambiental e Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.
authors.forename: Ricardo A
authors.initials: RA
authors.lastname: Zacarias Silva
authors.affiliation: Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM, Utrecht, The Netherlands.
authors.forename: Helena T A
authors.initials: HT
authors.lastname: van Tol
authors.affiliation: Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM, Utrecht, The Netherlands; Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM, Utrecht, The Netherlands.
authors.forename: Tom A E
authors.initials: TA
authors.lastname: Stout
authors.affiliation: Centro de Biologia Ambiental e Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Rodrigues
authors.affiliation: Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM, Utrecht, The Netherlands; Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM, Utrecht, The Netherlands.
authors.forename: Bernard A J
authors.initials: BA
authors.lastname: Roelen
mesh_terms: D000818:Animals; D064096:Aurora Kinase A / Q000378:metabolism; D001552:Benzazepines / Q000494:pharmacology; D001755:Blastocyst; D002417:Cattle; D008540:Meiosis / Q000235:genetics*; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000502:physiology*; D009865:Oocytes / Q000166:cytology* / Q000201:enzymology; D008941:Spindle Apparatus
chemical_list: D001552:Benzazepines; C518940:MLN8054; D008869:Microtubule-Associated Proteins; D064096:Aurora Kinase A