The fission yeast Cdc1 protein, a homologue of the small subunit of DNA polymerase delta, binds to Pol3 and Cdc27
The fission yeast Cdc1 protein, a homologue of the small subunit of DNA polymerase delta, binds to Pol3 and Cdc27
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DOI：
10.1002/j.1460-2075.1996.tb00839.x
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发表时间：
1996-09-02
期刊：
影响因子：
11.4
通讯作者：
Fantes, PA
中科院分区：
文献类型：
--
作者：
MacNeill, SA;Moreno, S;Fantes, PA
cdc1（+）在裂糖菌的细胞周期进程中是必需的。携带温度敏感的cdc1突变体的细胞在转移到限制性温度时发生细胞周期阻滞，变得高度延长。在这里，我们描述了cdc1（+）的克隆和测序，该cdc1（+）编码一个462残基蛋白，该蛋白与哺乳动物DNA聚合酶δ的小亚基具有显著的序列相似性。cdc1（+）与pol3（+）相互作用，pol3（+）在裂变酵母中编码DNA聚合酶delta的大亚基，并且cdc1蛋白在体外与pol3结合，强烈表明cdc1可能是Pol delta的小亚基。此外，我们发现cdc1 +过表达足以挽救携带温度敏感的cdc27等位基因的细胞，并且cdc1和cdc27蛋白在体内和体外相互作用。cdc1（+）或cdc27（+）的缺失导致细胞周期阻滞，被阻滞的细胞具有2C DNA含量的单核。没有证据表明cdc1（+）和cdc27（+）都不是检查点功能所必需的，cdc1突变细胞对DNA合成抑制剂羟基脲和DNA损伤剂MMS超敏感，显示小染色体丢失频率增加，S期延长。
cdc1(+) is required for cell cycle progression in Schizosaccharomyces pombe. Cells carrying temperature-sensitive cdc1 mutants undergo cell cycle arrest when shifted to the restrictive temperature, becoming highly elongated, Here we describe the cloning and sequencing of cdc1(+), which is shown to encode a 462 residue protein that displays significant sequence similarity to the small subunit of mammalian DNA polymerase delta. cdc1(+) interacts genetically with pol3(+), which encodes the large subunit of DNA polymerase delta in fission yeast, and the Cdc1 protein binds to pol3 in vitro, strongly suggesting that Cdc1 is likely to be the small subunit of Pol delta. In addition, we show that cdc1 + overexpression is sufficient to rescue cells carrying temperature-sensitive cdc27 alleles and that the Cdc1 and Cdc27 proteins interact in vivo and in vitro. Deletion of either cdc1(+) or cdc27(+) results in cell cycle arrest with the arrested cells having a single nucleus with 2C DNA content, No evidence was obtained for a cut phenotype, indicating that neither cdc1(+) nor cdc27(+) is required for checkpoint function, cdc1 mutant cells are supersensitive to the DNA synthesis inhibitor hydroxyurea and to the DNA damaging agent MMS, display increased frequency of mini-chromosome loss and have an extended S phase.