TACC3 Is Important for Correct Progression of Meiosis in Bovine Oocytes.
TACC3 Is Important for Correct Progression of Meiosis in Bovine Oocytes.
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DOI：
10.1371/journal.pone.0132591
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Roelen BA
中科院分区：
文献类型：
--
作者：
Mahdipour M;Leitoguinho AR;Zacarias Silva RA;van Tol HT;Stout TA;Rodrigues G;Roelen BA
转化酸性卷曲螺旋（TACC）蛋白是有丝分裂过程中通过稳定纺锤体的关键参与者。然而，TACCs在减数分裂过程中的作用尚不清楚。我们使用牛卵母细胞研究TACC 3在减数分裂过程中的表达和功能。使用qRT-PCR在牛卵母细胞减数分裂期间检测到TACC 3 mRNA，虽然它也在卵裂期胚胎中表达，但其表达在桑椹胚和囊胚期下调。使用免疫荧光来证明TACC 3与微管蛋白共定位在中期I和II纺锤体中。然而，TACC 3在第一次减数分裂的后期或末期未被检测到。已知Aurora A在有丝分裂细胞中磷酸化并激活TACC 3，其在减数分裂卵母细胞和植入前胚胎中显示出与TACC 3相似的基因表达模式。然而，极光A蛋白只是非常短暂的减数分裂纺锤体。药物抑制Aurora A活性可抑制TACC 3磷酸化，但不能阻止TACC 3在纺锤体中出现。然而，抑制Aurora A活性确实导致异常的减数分裂纺锤体形成和牛卵母细胞成熟受损。通过使用siRNA注射敲低TACC 3表达获得了类似的结果。这些结果表明，TACC 3是重要的稳定的减数分裂纺锤体，但磷酸化的TACC 3极光A是不需要其募集到减数分裂纺锤体，虽然不能排除其他激酶的TACC 3的磷酸化。
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.