Gene duplication in the genome of parasitic Giardia lamblia.
Gene duplication in the genome of parasitic Giardia lamblia.
复制标题
寄生兰氏贾第鞭毛虫基因组中的基因重复
DOI：
10.1186/1471-2148-10-49
复制
发表时间：
2010-02-17
影响因子：
3.4
通讯作者：
Wen J
中科院分区：
文献类型：
--
作者：
Sun J;Jiang H;Flores R;Wen J
背景
贾第鞭毛虫是许多脊椎动物中广泛分布的肠道原生动物寄生虫。来自兰伯利亚的大量证据表明它们可能是现存最原始的真核生物。这样一群最早的分支单细胞真核生物何时以及如何发展出成功寄生最新分支的高等真核生物（脊椎动物）的能力是一个有趣的问题。长期以来，基因复制一直被认为是进化新颖性起源的主要资源生产中最常见的机制。为了解析贾第鞭毛虫寄生生活方式的进化轨迹，我们对蓝氏贾第鞭毛虫的基因重复模式进行了全基因组分析。
结果
尽管基因组比较表明G.ambalia的许多基本生物学途径的内容被简化并且整个基因组非常紧凑，但在我们的研究中，其40%的基因被鉴定为重复基因。对这些重复基因的进化距离分析表明，G.ambalia基因组中发生了两轮大规模重复事件。对它们的功能注释进一步表明，最近复制的大多数基因都是 VSP（变异特异性表面蛋白），这对于贾第鞭毛虫在宿主中成功寄生生活至关重要。通过与其宿主的进化比较，发现G.ambalia中VSP的快速扩张与胎盘哺乳动物的进化辐射一致。
结论
基于对蓝氏贾第鞭毛虫重复基因的全基因组分析，我们发现基因重复对于贾第鞭毛虫寄生生活方式的起源和进化至关重要。最近，G.ambalia 特有的 VSP 的扩张与其宿主的增加是一致的。因此我们提出了一个假设：Giradia 主机的增加可能是 VSP 快速扩张的驱动力。
Background
Giardia are a group of widespread intestinal protozoan parasites in a number of vertebrates. Much evidence from G. lamblia indicated they might be the most primitive extant eukaryotes. When and how such a group of the earliest branching unicellular eukaryotes developed the ability to successfully parasitize the latest branching higher eukaryotes (vertebrates) is an intriguing question. Gene duplication has long been thought to be the most common mechanism in the production of primary resources for the origin of evolutionary novelties. In order to parse the evolutionary trajectory of Giardia parasitic lifestyle, here we carried out a genome-wide analysis about gene duplication patterns in G. lamblia.
Results
Although genomic comparison showed that in G. lamblia the contents of many fundamental biologic pathways are simplified and the whole genome is very compact, in our study 40% of its genes were identified as duplicated genes. Evolutionary distance analyses of these duplicated genes indicated two rounds of large scale duplication events had occurred in G. lamblia genome. Functional annotation of them further showed that the majority of recent duplicated genes are VSPs (Variant-specific Surface Proteins), which are essential for the successful parasitic life of Giardia in hosts. Based on evolutionary comparison with their hosts, it was found that the rapid expansion of VSPs in G. lamblia is consistent with the evolutionary radiation of placental mammals.
Conclusions
Based on the genome-wide analysis of duplicated genes in G. lamblia, we found that gene duplication was essential for the origin and evolution of Giardia parasitic lifestyle. The recent expansion of VSPs uniquely occurring in G. lamblia is consistent with the increment of its hosts. Therefore we proposed a hypothesis that the increment of Giradia hosts might be the driving force for the rapid expansion of VSPs.
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影响因子：
10.7
作者：
Marri, Pradeep Reddy;Hao, Weilong;Golding, G. Brian
通讯作者：
Golding, G. Brian
DOI：
10.1002/jez.b.21122
发表时间：
2007-01-15
影响因子：
2.2
作者：
Jiang, Huifeng;Liu, Dongyuan;Wang, Wen
通讯作者：
Wang, Wen
影响因子：
64.8
作者：
Elde NC;Child SJ;Geballe AP;Malik HS
通讯作者：
Malik HS
影响因子：
64.8
作者：
Acquisti, Claudia;Kleffe, Juergen;Collins, Sinead
通讯作者：
Collins, Sinead
DOI：
10.1073/pnas.0404319101
发表时间：
2004-09-28
影响因子：
11.1
作者：
Hittinger, CT;Rokas, A;Carroll, SB
通讯作者：
Carroll, SB