宿主-寄生虫相互作用在横向转位子跨类型的横向转移中的作用
Clément Gilbert1, Sarah Schaack, John K Pace
1Department of Biology, University of Texas, Arlington, Texas 76019, USA.
Nature
|April 30, 2010
概括
主体-寄生虫相互作用促进无脊椎动物和脊椎动物之间水平转移遗传物质,特别是转位子. 这个过程显著影响动物的基因组进化,包括疾病载体.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 寄生虫学的寄生虫学
背景情况:
- 水平转移 (HT) 是真核生物的一个关键的进化机制.
- 转子子是易受HT的移动遗传元素,但它们的跨物种传播途径尚不清楚.
- 宿主-寄生虫关系被假设为HT的媒介.
研究的目的:
- 研究宿主-寄生虫相互作用在无脊椎动物和脊椎动物之间的横向转移中所起的作用.
- 确定特定的转体子家族及其HT中涉及的宿主.
- 为HT提供证据,促进基因组进化.
主要方法:
- 对宿主和寄生虫基因组中的转子子家族进行比较基因组学分析.
- 遗传学分析以确定转位子的起源和关系.
- 在疾病载体如Rhodnius prolixus和Lymnaea stagnalis中识别转体子.
主要成果:
- 在Rhodnius prolixus和一系列四足动物宿主中发现了四个不同的转位子家族.
- 这些虫子转位子与哺乳动物宿主 (鱼,松鼠) 的高序列相同性和遗传学聚类.
- 在Lymnaea stagnalis中确定了一个转子家族,其序列类似于旧世界哺乳动物中的序列.
结论:
- 主体-寄生虫相互作用,特别是血液养和三级虫感染,促进无脊椎动物和脊椎动物之间的转位子HT.
- 横向转移的转子子的放大有助于动物的基因组进化.
- 这项研究提供了强有力的证据,证明了寄生虫相互作用在调解跨物种遗传交换中的作用.
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