RNA interference machinery regulates chromosome dynamics during mitosis and meiosis in fission yeast
RNA interference machinery regulates chromosome dynamics during mitosis and meiosis in fission yeast
复制标题
DOI：
10.1073/pnas.232688099
复制
发表时间：
2003-01-07
影响因子：
11.1
通讯作者：
Grewal, SIS
中科院分区：
文献类型：
--
作者：
Hall, IM;Noma, K;Grewal, SIS
高阶染色体结构的调节是细胞分裂和有性生殖的中心。着丝粒处的异染色质组装促进动粒形成和姐妹染色单体凝聚，并且端粒处特化染色质结构的形成用于维持端粒重复序列的长度，抑制重组，并且有助于形成促进减数分裂期间同源染色体配对的花束状结构。在裂殖酵母中，编码Argonaute、Dicer和参与RNA干扰（RNAi）的RNA依赖性RNA聚合酶因子的基因是在着丝粒和交配型区域形成异染色质所必需的。在这项研究中，我们研究了在有丝分裂和减数分裂过程中染色体动力学的裂变酵母RNAi机制的删除的影响。我们发现RNAi机制是染色体精确分离所必需的。有丝分裂染色体分离的缺陷与着丝粒内粘蛋白的丢失有关。虽然RNAi突变体的端粒保持沉默，长度和本地化的异染色质蛋白Swi6，我们发现缺陷的端粒在间期有丝分裂细胞中的正确聚类。此外，一小部分RNAi突变体细胞在减数分裂前期显示异常的端粒聚集。这项研究表明，分裂酵母RNAi机制是需要在有丝分裂和减数分裂染色体结构的适当调节。
The regulation of higher-order chromosome structure is central to cell division and sexual reproduction. Heterochromatin assembly at the centromeres facilitates both kinetochore formation and sister chromatid cohesion, and the formation of specialized chromatin structures at telomeres serves to maintain the length of telomeric repeats, to suppress recombination, and to aid in formation of a bouquet-like structure that facilitates homologous chromosome pairing during meiosis. In fission yeast, genes encoding the Argonaute, Dicer, and RNA-dependent RNA polymerase factors involved in RNA interference (RNAi) are required for heterochromatin formation at the centromeres and mating type region. In this study, we examine the effects of deletions of the fission yeast RNAi machinery on chromosome dynamics during mitosis and meiosis. We find that the RNAi machinery is required for the accurate segregation of chromosomes. Defects in mitotic chromosome segregation are correlated with loss of cohesin at centromeres. Although the telomeres of RNAi mutants maintain silencing, length, and localization of the heterochromatin protein Swi6, we discovered defects in the proper clustering of telomeres in interphase mitotic cells. Furthermore, a small proportion of RNAi mutant cells display aberrant telomere clustering during meiotic prophase. This study demonstrates that the fission yeast RNAi machinery is required for the proper regulation of chromosome architecture during mitosis and meiosis.