开花植物中的宿主-寄生虫基因转移:来自Malpighiales的家族遗传证据
Charles C Davis1, Kenneth J Wurdack
1Ecology and Evolutionary Biology, University of Michigan Herbarium, 3600 Varsity Drive, Ann Arbor, MI 48108-2287, USA. chdavis@umich.edu
Science (New York, N.Y.)
|July 17, 2004
概括
寄生性开花植物可能通过横向基因转移 (HGT) 从宿主中获得基因. 这项研究表明,寄生关系在植物中促进了HGT,为非相关物种之间基因交换提供了一种机制.
科学领域:
- 植物进化生物学 植物进化生物学
- 分子遗传学分子遗传学
- 基因组学就是基因组学.
背景情况:
- 横向基因转移 (HGT) 在更高的植物中得到了记录,但缺乏机械解释.
- 寄生植物为研究物种间基因转移提供了一个独特的模型.
- 拉弗莱西亚及其亲属 (Rafflesiaceae) 是 Malpighiales.序列中的内寄生虫.
研究的目的:
- 调查寄生关系在促进植物物种之间HGT的潜在作用.
- 用多基因分析来确定拉夫莱西亚系的遗传位置.
- 探索通过HGT在Rafflesiaceae中获得线粒体基因组的证据.
主要方法:
- 使用线粒体 (matR,nad1B-C) 和核 (18S核糖体DNA,PHYC) 位点进行了多基因遗传学分析.
- 遗传树是为了推断进化关系而构建的.
- 分析了不一致的家族遗传位置,以确定潜在的HGT事件.
主要成果:
- 核和一些线粒体基因将拉夫莱西亚系置于Malpighiales中,靠近Ochnaceae/Clusiaceae.
- 一个不同的线粒体基因 (nad1B-C) 将拉夫莱西亚群归入维塔系,与它们的宿主属Tetrastigma有密切的关系.
- 这些相互矛盾的遗传学信号强烈表明线粒体DNA的HGT.
结论:
- 寄生植物与宿主之间的相互作用可以促进线粒体基因组的水平基因转移.
- 拉弗莱西亚家族很可能从它们的宿主植物 (Tetrastigma) 中获得了它们的线粒体基因组的一部分.
- 这项研究提供了花植物中HGT的机制解释,由寄生虫驱动.
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