Departamento de Biología, Facultad de Ciencias, Unidad de Biología Celular, Universidad Autónoma de Madrid, Madrid, Spain.
Cell Division and Cancer Group, Spanish National Cancer Research Centre (CNIO), Madrid, Spain.
EMBO Rep. 2021 Apr 7;22(4):e51030. doi: 10.15252/embr.202051030. Epub 2021 Feb 21.
Cell division requires the regulation of karyokinesis and cytokinesis, which includes an essential role of the achromatic spindle. Although the functions of centrosomes are well characterised in somatic cells, their role during vertebrate spermatogenesis remains elusive. We have studied the dynamics of the meiotic centrosomes in male mouse during both meiotic divisions. Results show that meiotic centrosomes duplicate twice: first duplication occurs in the leptotene/zygotene transition, while the second occurs in interkinesis. The maturation of duplicated centrosomes during the early stages of prophase I and II are followed by their separation and migration to opposite poles to form bipolar spindles I and II. The study of the genetic mouse model Plk1(Δ/Δ) indicates a central role of Polo-like kinase 1 in pericentriolar matrix assembly, in centrosome maturation and migration, and in the formation of the bipolar spindles during spermatogenesis. In addition, in vitro inhibition of Polo-like kinase 1 and Aurora A in organotypic cultures of seminiferous tubules points out to a prominent role of both kinases in the regulation of the formation of meiotic bipolar spindles.
细胞分裂需要调节核分裂和胞质分裂，这包括无丝分裂纺锤体的重要作用。尽管中心体的功能在体细胞中得到了很好的描述，但它们在脊椎动物精子发生过程中的作用仍然难以捉摸。我们研究了雄性小鼠减数分裂过程中减数分裂中心体的动力学。结果表明，减数分裂中心体发生两次复制：第一次复制发生在细线期/合线期转换，而第二次复制发生在间期间期。复制的中心体在前期 I 和 II 的早期阶段成熟后，分离并迁移到相对的两极，形成两极纺锤体 I 和 II。对 Plk1(Δ/Δ)基因敲除小鼠模型的研究表明，Polo 样激酶 1 在中心体周围基质组装、中心体成熟和迁移以及精子发生过程中两极纺锤体的形成中起着核心作用。此外，在生精小管器官型培养物中抑制 Polo 样激酶 1 和 Aurora A，指出这两种激酶在调节减数分裂两极纺锤体形成中起着重要作用。
