Kiburz Brendan M, Amon Angelika, Marston Adele L
Center for Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Mol Biol Cell. 2008 Mar;19(3):1199-209. doi: 10.1091/mbc.e07-06-0584. Epub 2007 Dec 19.
Chromosome segregation must be executed accurately during both mitotic and meiotic cell divisions. Sgo1 plays a key role in ensuring faithful chromosome segregation in at least two ways. During meiosis this protein regulates the removal of cohesins, the proteins that hold sister chromatids together, from chromosomes. During mitosis, Sgo1 is required for sensing the absence of tension caused by sister kinetochores not being attached to microtubules emanating from opposite poles. Here we describe a differential requirement for Sgo1 in the segregation of homologous chromosomes and sister chromatids. Sgo1 plays only a minor role in segregating homologous chromosomes at meiosis I. In contrast, Sgo1 is important to bias sister kinetochores toward biorientation. We suggest that Sgo1 acts at sister kinetochores to promote their biorientation.
在有丝分裂和减数分裂细胞分裂过程中，染色体分离都必须精确执行。Sgo1至少通过两种方式在确保染色体忠实分离方面发挥关键作用。在减数分裂期间，这种蛋白质调节着黏连蛋白（将姐妹染色单体结合在一起的蛋白质）从染色体上的去除。在有丝分裂期间，Sgo1对于感知姐妹动粒未附着于来自相对两极的微管而导致的张力缺失是必需的。在这里，我们描述了Sgo1在同源染色体和姐妹染色单体分离中的不同需求。Sgo1在减数分裂I中同源染色体的分离中仅起次要作用。相比之下，Sgo1对于使姐妹动粒偏向双定向是很重要的。我们认为Sgo1在姐妹动粒处起作用以促进它们的双定向。
