...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of bacteriology >Inhibition of Agrobacterium tumefaciens oncogenicity by the osa gene of pSa.
【24h】

Inhibition of Agrobacterium tumefaciens oncogenicity by the osa gene of pSa.

机译：pSa osa基因抑制根癌农杆菌致癌性。

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

摘要

The IncW plasmid pSa originally derived from Shigella flexneri completely inhibits the tumor-inducing ability of Agrobacterium tumefaciens when it is resident in this organism. Oncogenic inhibition is mediated through the expression of the osa gene on pSa. This gene is part of a 3.1-kb DNA segment of pSa that contains four open reading frames revealed by sequencing. Specific deletions and TnCAT insertions within this segment localized the oncogenic inhibitory activity to the last open reading frame, orf-4, designated osa (for oncogenic suppression activity). No promoter exists immediately upstream of the coding sequence of osa since TnCAT insertions or deletions into orf-3 caused the loss of oncogenic inhibition. Deletion analysis showed that the promoter of orf-1 is required for osa transcription. The first three orfs have no role in oncogenic inhibition, since osa alone placed under the control of a constitutive Pkm promoter completely inhibited A. tumefaciens oncogenicity. This inhibition of oncogenicity by osa is not limited to a specific host plant but appears to show broad host specificity. Because the osa-encoded product has close homologies to the fiwA-encoded product of the IncP plasmid RP1, osa may be involved in fertility inhibition that would prevent or reduce the formation of stable mating pairs and T-DNA transfer between A. tumefaciens and plants.
机译：当原产于弗氏志贺氏菌的IncW质粒pSa完全位于根癌农杆菌中时，它会完全抑制它的肿瘤诱导能力。致癌抑制作用是通过在pSa上表达osa基因介导的。该基因是pSa的3.1 kb DNA片段的一部分，该片段包含通过测序揭示的四个开放阅读框。在该片段内的特定缺失和TnCAT插入将致癌抑制活性定位于最后一个开放阅读框orf-4（称为osa）（用于致癌抑制活性）。由于TnCAT在orf-3中的插入或缺失会导致致癌抑制作用的丧失，因此在osa编码序列的上游没有启动子存在。缺失分析表明，orf-1的启动子是osa转录所必需的。前三个orf在致癌性抑制中没有作用，因为仅将osa置于组成性Pkm启动子的控制下完全抑制了根癌农杆菌的致癌性。 osa对致癌性的抑制作用不仅限于特定的宿主植物，而且似乎显示出广泛的宿主特异性。由于osa编码产物与IncP质粒RP1的fiwA编码产物具有相似的同源性，因此osa可能参与生育抑制，这将阻止或减少稳定交配对的形成以及根癌农杆菌和植物之间的T-DNA转移。 。

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