CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100029, China.
J Genet Genomics. 2011 Feb;38(2):63-70. doi: 10.1016/j.jcg.2011.01.003. Epub 2011 Feb 23.
Transposons are sequence elements widely distributed among genomes of all three kingdoms of life, providing genomic changes and playing significant roles in genome evolution. Trichomonas vaginalis is an excellent model system for transposon study since its genome (~160 Mb) has been sequenced and is composed of ~65% transposons and other repetitive elements. In this study, we primarily report the identification of Kolobok-type transposons (termed tvBac) in T. vaginalis and the results of transposase sequence analysis. We categorized 24 novel subfamilies of the Kolobok element, including one autonomous subfamily and 23 non-autonomous subfamilies. We also identified a novel H2CH motif in tvBac transposases based on multiple sequence alignment. In addition, we supposed that tvBac and Mutator transposons may have evolved independently from a common ancestor according to our phylogenetic analysis. Our results provide basic information for the understanding of the function and evolution of tvBac transposons in particular and other related transposon families in general.
转座子广泛分布于所有三个生命王国的基因组中，提供基因组变化，并在基因组进化中发挥重要作用。阴道毛滴虫是转座子研究的一个极好的模型系统，因为其基因组 (~160Mb) 已经测序，并且由 ~65%的转座子和其他重复元件组成。在这项研究中，我们主要报告了在阴道毛滴虫中鉴定出 Kolobok 型转座子（称为 tvBac）的情况，以及转座酶序列分析的结果。我们对 Kolobok 元件的 24 个新亚家族进行了分类，包括一个自主亚家族和 23 个非自主亚家族。我们还根据多序列比对在 tvBac 转座酶中鉴定出一个新的 H2CH 基序。此外，根据系统发育分析，我们推测 tvBac 和 Mutator 转座子可能是从一个共同的祖先独立进化而来的。我们的研究结果为理解 tvBac 转座子在特定情况下以及其他相关转座子家族在一般情况下的功能和进化提供了基础信息。
