Cooper J P, Watanabe Y, Nurse P
Cell Cycle Laboratory, Imperial Cancer Research Fund, London, UK.
Nature. 1998 Apr 23;392(6678):828-31. doi: 10.1038/33947.
The alignment of homologous chromosomes during meiosis is essential for their recombination and segregation. Telomeres form and protect the ends of eukaryotic linear chromosomes, and are composed of tandem repeats of a simple DNA sequence and the proteins that bind to these repeats. A role for telomeres in meiosis was suspected from observations of telomere clustering in meiotic cells, and has now been supported experimentally by the dramatic rearrangement of telomere locations during premeiotic stages in fission yeast. Here we show that the fission yeast telomere protein, Taz1, is required for stable association between telomeres and spindle pole bodies during meiotic prophase. In the absence of Taz1, telomere clustering at the spindle pole bodies is disrupted, meiotic recombination is reduced, and both spore viability and the ability of zygotes to re-enter mitosis are impaired to a level that would be expected if chromosome segregation were occurring randomly. Such telomeric association mediated by telomere-specific proteins may also be important for proper chromosome alignment and recombination during meiosis in humans.
减数分裂过程中同源染色体的配对对于它们的重组和分离至关重要。端粒形成并保护真核生物线性染色体的末端,由简单DNA序列的串联重复序列以及与这些重复序列结合的蛋白质组成。从减数分裂细胞中端粒聚集的观察结果怀疑端粒在减数分裂中起作用,现在通过裂殖酵母减数分裂前期端粒位置的剧烈重排得到了实验支持。在这里,我们表明裂殖酵母端粒蛋白Taz1是减数分裂前期端粒与纺锤体极体之间稳定结合所必需的。在没有Taz1的情况下,纺锤体极体处的端粒聚集被破坏,减数分裂重组减少,并且孢子活力和受精卵重新进入有丝分裂的能力均受损至如果染色体随机分离所预期的水平。由端粒特异性蛋白介导的这种端粒结合对于人类减数分裂过程中正确的染色体配对和重组也可能很重要。