...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Molecular and Cellular Biology >Concerted evolution at a multicopy locus in the protozoan parasite Theileria parva: extreme divergence of potential protein-coding sequences.
【24h】

Concerted evolution at a multicopy locus in the protozoan parasite Theileria parva: extreme divergence of potential protein-coding sequences.

机译：在原生动物寄生虫Theileria parva的多拷贝基因座上的协同进化：潜在蛋白质编码序列的极端分歧。

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

摘要

Concerted evolution of multicopy gene families in vertebrates is recognized as an important force in the generation of biological novelty but has not been documented for the multicopy genes of protozoa. A multicopy locus, Tpr, which consists of tandemly arrayed open reading frames (ORFs) containing several repeated elements has been described for Theileria parva. Herein we show that probes derived from the 5'/N-terminal ends of ORFs in the genomic DNAs of T. parva Uganda (1,108 codons) and Boleni (699 codons) hybridized with multicopy sequences in homologous DNA but did not detect similar sequences in the DNA of 14 heterologous T. parva stocks and clones. The probe sequences were, however, protein coding according to predictive algorithms and codon usage. The 3'/C-terminal ends of the Uganda and Boleni ORFs exhibited 75% similarity and identity, respectively, to the previously identified Tpr1 and Tpr2 repetitive elements of T. parva Muguga. Tpr1-homologous sequences were detected in two additional species of Theileria. Eight different Tpr1-homologous transcripts were present in piroplasm mRNA from a single T. parva Muguga-infected animal. The Tpr1 and Tpr2 amino acid sequences contained six predicted membrane-associated segments. The ratio of synonymous to nonsynonymous substitutions indicates that Tpr1 evolves like protein-encoding DNA. The previously determined nucleotide sequence of the gene encoding the p67 antigen is completely identical in T. parva Muguga, Boleni, and Uganda, including the third base in codons. The data suggest that concerted evolution can lead to the radical divergence of coding sequences and that this can be a mechanism for the generation of novel genes.
机译：脊椎动物中多拷贝基因家族的协调进化被认为是产生生物新颖性的重要力量，但尚未有原生动物多拷贝基因的文献报道。对于泰勒虫小孢子，已经描述了多拷贝基因座TPr，其由包含几个重复元件的串联排列的开放阅读框（ORF）组成。本文中，我们显示了源自乌龟（T. parva Uganda）（1,108个密码子）和博莱尼（699个密码子）的基因组DNA中ORFs 5'/ N末端的探针与同源DNA中的多拷贝序列杂交，但未检测到相似的序列。 14种异源丁香球菌种群和克隆的DNA。然而，根据预测算法和密码子使用，探针序列是蛋白质编码。乌干达和Boleni ORF的3'/ C末端分别与先前鉴定的T. parva Muguga的Tpr1和Tpr2重复元件表现出75％的相似性和同一性。在两个其他的泰勒虫物种中检测到Tpr1同源序列。八种不同的Tpr1同源转录本存在于来自感染了T. parva Muguga的一只动物的质体mRNA中。 Tpr1和Tpr2氨基酸序列包含六个预测的膜相关节段。同义与非同义取代的比率表明Tpr1像编码蛋白质的DNA一样进化。先前确定的编码p67抗原的基因的核苷酸序列在T. parva Muguga，Boleni和Uganda中完全相同，包括密码子中的第三个碱基。数据表明，协同进化可以导致编码序列的根本分歧，并且这可能是产生新基因的机制。

著录项

相似文献

  • 外文文献
  • 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