• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >Origin and evolutionary process of the CNS elucidated by comparative genomics analysis of planarian ESTs
【24h】

Origin and evolutionary process of the CNS elucidated by comparative genomics analysis of planarian ESTs

机译：通过平面涡流EST的比较基因组学分析阐明了CNS的起源和进化过程

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Among the bilateral animals, a centralized nervous system is found in both the deuterostome and protostome. To address the question of whether the CNS was derived from a common ancestor of deuterostomes and protostomes, it is essential to know kinds of genes existed in the CNS of the putative common ancestor and to trace the evolutionary divergence of genes expressed in the CNS. To answer these questions, we took a comparative approach using different species, particularly focusing on one of the lower bilateral animals, the planarian (Platyhelminthes, Tricladida), which is known to possess a CNS. We determined the nucleotide sequence of ESTs from the head portion of planarians, obtaining 3,101 nonredundant EST clones. As a result of homology searches, we found that 116 clones had significant similarity to known genes related to the nervous system. Here, we compared these 116 planarian EST clones with all ORFs of the complete genome sequences of the human, fruit fly, and nematode, and showed that >95% of these 116 nervous system-related genes, including genes involved in brain or neural morphogenesis, were commonly shared among these organisms, thus providing evidence at the molecular level for the existence of a common ancestral CNS. Interestingly, we found that approximate to30% of planarian nervous system-related genes had homologous sequences in Arabidopsis and yeast, which do not possess a nervous system. This implies that the origin of nervous system-related genes greatly predated the emergence of the nervous system, and that these genes might have been recruited toward the nervous system. [References: 33]
机译：在双侧动物中，氘吻口和前吻口都发现了中枢神经系统。为了解决CNS是否源自氘吻合器和原生动物的共同祖先的问题，必须了解假定的共同祖先的CNS中存在的各种基因，并追踪CNS中表达的基因的进化差异。为了回答这些问题，我们采用了一种比较方法，使用了不同的物种，特别是侧重于一只较低的双侧动物，即涡卷虫（Platyhelminthes，Tricladida），它具有中枢神经系统。我们从涡虫的头部确定了EST的核苷酸序列，获得了3101个非冗余EST克隆。同源搜索的结果是，我们发现116个克隆与与神经系统有关的已知基因具有显着相似性。在这里，我们将这116个平面虫EST克隆与人类，果蝇和线虫的完整基因组序列的所有ORF进行了比较，结果表明，在这116个神经系统相关基因中，> 95％包括与大脑或神经形态发生有关的基因在这些生物中通常共享，因此在分子水平上提供了共同祖先中枢神经系统存在的证据。有趣的是，我们发现大约30％的与涡虫神经系统相关的基因在拟南芥和酵母中具有同源序列，而它们不具有神经系统。这意味着与神经系统相关的基因的起源大大早于神经系统的出现，并且这些基因可能已经被募集到神经系统中。 [参考：33]

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