...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Molecular and Cellular Biology >NDD1, a High-Dosage Suppressor ofcdc28-1N, Is Essential for Expression of a Subset of Late-S-Phase-Specific Genes in Saccharomyces cerevisiae
【24h】

NDD1, a High-Dosage Suppressor ofcdc28-1N, Is Essential for Expression of a Subset of Late-S-Phase-Specific Genes in Saccharomyces cerevisiae

机译：NDD1，cdc28-1N的高剂量抑制剂，对于酿酒酵母中后期S期特定基因的子集的表达至关重要

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

cdc28-1N mutants progress through the G1and S phases normally at the restrictive temperature but fail to undergo nuclear division. We have isolated a gene, NDD1, which at a high dosage suppresses the nuclear-division defect ofcdc28-1N. NDD1 (nuclear division defective) is an essential gene. Its expression during the cell cycle is tightly regulated such that NDD1 RNA is most abundant during the S phase. Cells lacking the NDD1 gene arrest with an elongated bud, a short mitotic spindle, 2N DNA content, and an undivided nucleus, suggesting that its function is required for some aspect of nuclear division. We show that overexpression of Ndd1 results in the upregulation of bothCLB1 and CLB2 transcription, suggesting that the suppression of cdc28-1N by NDD1 may be due to an accumulation of these cyclins. Overproduction of Ndd1 also enhances the expression of SWI5, whose transcription, like that of CLB1 and CLB2, is activated in the late S phase. Ndd1 is essential for the expression of CLB1,CLB2, and SWI5, since none of these genes are transcribed in its absence. Both CLB2 expression and its upregulation by NDD1 are mediated by a 240-bp promoter sequence that contains four MCM1-binding sites. However, Ndd1 does not appear to be a component of any of the protein complexes assembled on this DNA fragment, as indicated by gel mobility shift assays. Instead, overexpression of NDD1 prevents the formation of one of the complexes whose appearance correlates with the termination of CLB2 expression in G1. The inability of GAL1 promoter-driven CLB2 to suppress the lethality of NDD1 null mutant suggests that, in addition to CLB1 and CLB2, NDD1may also be required for the transcription of other genes whose functions are necessary for G2/M transition.
机译： cdc28-1N 突变体通常在限制性温度下经历G 1 和S期，但不能进行核分裂。我们已经分离出一个基因， NDD1 ，该基因以高剂量抑制了 cdc28-1N的核分裂缺陷。 NDD1 （核分裂缺陷）是必需基因。它在细胞周期中的表达受到严格调节，以致 NDD1 RNA在S期最丰富。缺少 NDD1 基因的细胞会因芽伸长，有丝分裂纺锤体短，2N DNA含量和未分裂的核而停滞，表明其功能是核分裂的某些方面所必需的。我们发现Ndd1的过表达导致 CLB1 和 CLB2 转录的上调，表明 cdc28-1N 被抑制NDD1 可能是由于这些细胞周期蛋白的积累。 Ndd1的过量生产还增强了 SWI5 的表达，其转录与 CLB1 和 CLB2 一样，在S期后期被激活。 Ndd1对于 CLB1 ， CLB2 和 SWI5 的表达至关重要，因为这些基因在不存在的情况下都不会被转录。 CLB2 的表达及其由 NDD1 的上调均由包含四个 MCM1 结合位点的240 bp启动子序列介导。但是，Ndd1似乎不是组装在该DNA片段上的任何蛋白质复合物的组成部分，如凝胶迁移率移动分析所示。取而代之的是， NDD1 的过度表达可阻止形成外观与G 1 中 CLB2 表达终止相关的复合物之一。 GAL1 启动子驱动的 CLB2 不能抑制 NDD1 空突变体的致死性，这表明，除了 CLB1 和 CLB2 ， NDD1 也可能是转录G 2 / M过渡所必需的其他基因所必需的。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号