A conserved protein, Nuf2, is implicated in connecting the centromere to the spindle during chromosome segregation: a link between the kinetochore function and the spindle checkpoint
A conserved protein, Nuf2, is implicated in connecting the centromere to the spindle during chromosome segregation: a link between the kinetochore function and the spindle checkpoint
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DOI：
10.1007/s004120100153
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发表时间：
2001-09-01
期刊：
影响因子：
1.6
通讯作者：
Hiraoka, Y
中科院分区：
文献类型：
--
作者：
Nabetani, A;Koujin, T;Hiraoka, Y
着丝粒对于所有真核细胞中染色体的正确分离至关重要。我们鉴定了一种着丝粒蛋白 Nuf2，它在裂殖酵母、人类、线虫和芽殖酵母中保守。裂殖酵母粟酒裂殖酵母中 nuf2(+) 的基因破坏导致染色体分离和纺锤体检查点缺陷：有丝分裂纺锤体伸长但染色体不分离，表明纺锤体功能受到损害，但这种异常并未导致中期停滞。然而，某些 nuf2 温度敏感突变会导致中期停滞，染色体浓缩和纺锤体短，这表明，虽然这些突变导致纺锤体功能异常，但纺锤体检查点途径保持完整。这些细胞的中期停滞依赖于纺锤体检查点成分 Mad2。有趣的是，当着丝粒失去与纺锤体极体的连接时，Nuf2 在减数分裂前期从着丝粒中消失。我们认为 Nuf2 在着丝粒上发挥作用，与纺锤体建立连接以实现正确的染色体分离，并且 Nuf2 功能也是纺锤体检查点所必需的。
The centromere is crucial for the proper segregation of chromosomes in all eukaryotic cells. We identified a centromeric protein, Nuf2, which is conserved in fission yeast, human, nematode, and budding yeast. Gene disruption of nuf2(+) in the fission yeast Schizosaccharomyces pombe caused defects in chromosome segregation and the spindle checkpoint: the mitotic spindle elongated without segregating the chromosomes, indicating that spindle function was compromised, but that this abnormality did not result in metaphase arrest. Certain nuf2 temperature-sensitive mutations, however, caused metaphase arrest with condensed chromosomes and a short spindle, indicating that, while these mutations caused abnormalities in spindle function, the spindle checkpoint pathway remained intact. Metaphase arrest in these cells was dependent on the spindle checkpoint component Mad2. Interestingly, Nuf2 disappeared from the centromere during meiotic prophase when centromeres lose their connection to the spindle pole body. We propose that Nuf2 acts at the centromere to establish a connection with the spindle for proper chromosome segregation, and that Nuf2 function is also required for the spindle checkpoint.