Institute of Evolutionary Biology, University of Edinburgh, Edinburgh EH9 3JT, UK.
Mol Ecol Resour. 2011 May;11(3):521-9. doi: 10.1111/j.1755-0998.2010.02956.x. Epub 2010 Dec 20.
Increasing numbers of phylogeographic studies make comparative inferences about the histories of co-distributed species. Although the aims of such studies are best achieved by jointly analysing sequences from multiple loci in a model-based framework, such data currently exist for few nonmodel systems. We used existing genomic data and expressed sequence tags (ESTs) for Hymenoptera and other insects to design intron-crossing primers for 40 loci, mainly ribosomal proteins, for chalcidoid parasitoids. Amplification success was scored on a range of taxa associated with two natural communities; oak galls and figs. Taxa were chosen at increasing distance from Nasonia, which was used for primer design, (i) within Pteromalids, (ii) within Chalcidoidea (Eupelmidae, Eulophidae, Eurytomidae, Ormyridae, Torymidae) and (iii) for a selection of distantly related gall and fig wasps (Cynipidae, Agaonidae). To assess the utility of these loci for phylogeographic and population genetic studies, we compared genetic diversity between Western Palaearctic refugia for two species. Our results show that it is feasible to design a large number of exon-primed-intron-crossing (EPIC) loci that may be informative about phylogeographic history within species but amplify across a large taxonomic range.
越来越多的系统地理学研究对共分布物种的历史进行了比较推断。虽然此类研究的目标最好通过在基于模型的框架中联合分析多个基因座的序列来实现,但这种数据目前很少存在于非模型系统中。我们使用膜翅目昆虫和其他昆虫的现有基因组数据和表达序列标签(EST),为拟寄生物的 40 个基因座(主要是核糖体蛋白)设计了内含子跨越引物。在与两个自然群落(栎瘿蜂和榕小蜂)相关的一系列分类群中,我们对扩增成功率进行了评分。选择的分类群与用于引物设计的纳索尼亚(Nasonia)的距离越来越远,(i)在 Pteromalids 中,(ii)在 Chalcidoidea(Eupelmidae、Eulophidae、Eurytomidae、Ormyridae、 Torymidae)中,以及(iii)为选择的亲缘关系较远的瘿蜂和榕小蜂( Cynipidae、Agaonidae)。为了评估这些基因座在系统地理学和种群遗传学研究中的实用性,我们比较了两个物种在西古北区避难所之间的遗传多样性。我们的结果表明,设计大量的外显子引物-内含子跨越(EPIC)基因座是可行的,这些基因座可能对物种内的系统地理学历史有信息价值,但可以在很大的分类范围内扩增。