Pds1p is required for faithful execution of anaphase in the yeast, Saccharomyces cerevisiae.
Pds1p is required for faithful execution of anaphase in the yeast, Saccharomyces cerevisiae.
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Pds1p 是酿酒酵母后期忠实执行所必需的。
DOI：
10.1083/jcb.133.1.85
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Koshland,D
中科院分区：
文献类型：
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作者：
Yamamoto,A;Guacci,V;Koshland,D
为了鉴定导致有丝分裂缺陷的突变，通过快速目视分析异常染色体分离来筛选酿酒酵母中的突变体集合。从该筛选中，我们鉴定了一种突变，即在另一种筛选中独立鉴定的突变体，所述突变体在短暂暴露于诺考达唑后表现出失活性和姐妹染色单体的过早解离（Guacci，V.，a. Yamamoto，A. Strunnikov，J. Kingsbury，E. Hogan，P. Meluh，and D.科什兰1993. CSH Symp.定量58：677 - 685; Yamamoto，T.J.，G.李，B。沙尔岛Szilak和D.W.克利夫兰1992.自然（伦敦）。359：536 - 539）。在23摄氏度下，与野生型相比，<$1 - 1突变体表现出频繁的细胞死亡和300倍的染色体丢失。在37摄氏度时，<$1 - 1细胞在分裂后期不能伸长它们的纺锤体。这种纺锤体缺陷是由于在纺锤体组装时G1/S边界附近发生的温度敏感步骤引起的。在缺乏纺锤体伸长的情况下，突1突变体进行胞质分裂，导致染色体和纺锤体极体的错误分离。在细胞分裂异常后，突1 - 1突变体还启动新一轮的DNA复制、纺锤体极体复制和芽形成。因此，在37摄氏度下，在突1 - 1突变体中，细胞周期进程与后期的完成是不偶联的。1缺失等位基因具有与原始等位基因相似的表型。综上所述，这些结果表明，Pds 1蛋白在23 ℃时在染色体分离中起重要作用，在37 ℃时对该过程起重要作用。PDS1基因编码一种新的42 kD核蛋白，具有碱性和酸性结构域。PDS1 mRNA水平随细胞周期而变化，在G1/S边界附近最大积聚。Pds1蛋白的稳定性似乎也在细胞周期中发生变化，因为过度产生的Pds1p在S和M中是稳定的，但在G1早期降解。因此，在细胞周期中，Pds1p的表达明显受到转录和翻译后的调节。在其它纺锤体缺陷型突变体和Pds 1蛋白是后期抑制剂的知识的背景下讨论了Pds 1突变体的表型和Pds 1 p的表达模式（Yamamoto，T.J.，G.李，B。沙尔岛Szilak和D.W.克利夫兰1992.自然（伦敦）。359：536 - 539）。
To identify mutations that cause defects in mitosis, a collection of mutants in Saccharomyces cerevisiae was screened by a rapid visual assay for abnormal chromosome segregation. From this screen we identified one mutation, pds1-1 that was independently identified in an alternative screen for mutants that exhibit inviability after transient exposure to nocodazole and precocious disassociation of sister chromatids (Guacci, V., A. Yamamoto, A. Strunnikov, J. Kingsbury, E. Hogan, P. Meluh, and D. Koshland. 1993. CSH Symp. Quant. Biol. 58:677-685; Yamamoto, T.J., G. Li, B. Schaar, I. Szilak, and D.W. Cleveland. 1992. Nature (Lond.). 359:536-539). At 23 degrees C pds1-1 mutants exhibit frequent cell death and a 300-fold increase in chromosome loss compared to wild type. At 37 degrees C pds1-1 cells fail to elongate their spindles during anaphase. This spindle defect of pds1 mutants results from a temperature-sensitive step that occurs around the G1/S boundary about the time of spindle assembly. In the absence of spindle elongation pds1 mutants undergo cytokinesis, leading to the missegregation of both chromosomes and spindle pole bodies. After abnormal cell division pds1-1 mutants also initiate new rounds of DNA replication, spindle pole body duplication, and bud formation. Thus, in the pds1-1 mutant at 37 degrees C, cell cycle progression is uncoupled from the completion of anaphase. A pds1 deletion allele has similar phenotypes to the original allele. Taken together these results suggest that Pds1 protein plays an important role in chromosome segregation at 23 degrees C and an essential role for this process at 37 degrees C. The PDS1 gene encodes a novel 42-kD nuclear protein that has both basic and acidic domains. The level of PDS1 mRNA varies with the cell cycle with maximal accumulation around the G1/S boundary. The stability of Pds1 protein also appears to change during the cell cycle as overproduced Pds1p is stable in S and M but degraded in early G1. Therefore, expression of Pds1p is regulated apparently both transcriptionally and postranslationally during the cell cycle. The phenotypes of pds1 mutants and expression pattern of Pds1p are discussed in the context of other spindle-defective mutants and the knowledge that Pds1 protein is an inhibitor of anaphase (Yamamoto, T.J., G. Li, B. Schaar, I. Szilak, and D.W. Cleveland. 1992. Nature (Lond.). 359:536-539).