Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195, USA.
Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, UK.
Science. 2014 Oct 10;346(6206):248-51. doi: 10.1126/science.1256729. Epub 2014 Sep 11.
Production of healthy gametes requires a reductional meiosis I division in which replicated sister chromatids comigrate, rather than separate as in mitosis or meiosis II. Fusion of sister kinetochores during meiosis I may underlie sister chromatid comigration in diverse organisms, but direct evidence for such fusion has been lacking. We used laser trapping and quantitative fluorescence microscopy to study native kinetochore particles isolated from yeast. Meiosis I kinetochores formed stronger attachments and carried more microtubule-binding elements than kinetochores isolated from cells in mitosis or meiosis II. The meiosis I-specific monopolin complex was both necessary and sufficient to drive these modifications. Thus, kinetochore fusion directs sister chromatid comigration, a conserved feature of meiosis that is fundamental to Mendelian inheritance.
健康配子的产生需要减数分裂 I 分裂，在此过程中复制的姐妹染色单体同源迁移，而不是像有丝分裂或减数分裂 II 那样分离。姐妹动粒在减数分裂 I 期间的融合可能是不同生物中姐妹染色单体同源迁移的基础，但缺乏这种融合的直接证据。我们使用激光捕获和定量荧光显微镜研究了从酵母中分离的天然动粒颗粒。与有丝分裂或减数分裂 II 细胞分离的动粒相比，减数分裂 I 动粒形成了更强的附着，并携带了更多的微管结合元件。减数分裂 I 特异性的单极复合物既是必需的，也是充分的，可驱动这些修饰。因此，动粒融合指导姐妹染色单体同源迁移，这是减数分裂的一个保守特征，对孟德尔遗传至关重要。
