Department of Biology, University of Rochester, Rochester, NY 14627, USA.
Heredity (Edinb). 2010 Mar;104(3):270-7. doi: 10.1038/hdy.2009.145. Epub 2010 Jan 20.
The genetic basis of host preference has been investigated in only a few species. It is relevant to important questions in evolutionary biology, including sympatric speciation, generalist versus specialist adaptation, and parasite-host co-evolution. Here we show that a major locus strongly influences host preference in Nasonia. Nasonia are parasitic wasps that utilize fly pupae; Nasonia vitripennis is a generalist that parasitizes a diverse set of hosts, whereas Nasonia giraulti specializes in Protocalliphora (bird blowflies). In laboratory choice experiments using Protocalliphora and Sarcophaga (flesh flies), N. vitripennis shows a preference for Sarcophaga, whereas N. giraulti shows a preference for Protocalliphora. Through a series of interspecies crosses, we have introgressed a major locus affecting host preference from N. giraulti into N. vitripennis. The N. giraulti allele is dominant and greatly increases preference for Protocalliphora pupae in the introgression line relative to the recessive N. vitripennis allele. Through the utilization of a Nasonia genotyping microarray, we have identified the introgressed region as 16 Mb of chromosome 4, although a more complete analysis is necessary to determine the exact genetic architecture of host preference in the genus. To our knowledge, this is the first introgression of the host preference of one parasitoid species into another, as well as one of the few cases of introgression of a behavioral gene between species.
宿主偏好的遗传基础仅在少数几个物种中进行了研究。它与进化生物学中的一些重要问题有关，包括同域物种形成、广食性与特化适应以及寄生虫-宿主共同进化。在这里，我们表明一个主要基因座强烈影响了 Nasonia 的宿主偏好。Nasonia 是一种寄生蜂，利用蝇蛹；Nasonia vitripennis 是一种广食性寄生虫，寄生在各种宿主上，而 Nasonia giraulti 则专门寄生在 Protocalliphora（鸟蝇）上。在使用 Protocalliphora 和 Sarcophaga（肉蝇）进行的实验室选择实验中，N. vitripennis 表现出对 Sarcophaga 的偏好，而 N. giraulti 则表现出对 Protocalliphora 的偏好。通过一系列种间杂交，我们已经将影响宿主偏好的一个主要基因座从 N. giraulti 引入到 N. vitripennis 中。N. giraulti 等位基因是显性的，与 N. vitripennis 的隐性等位基因相比，在导入系中大大增加了对 Protocalliphora 蛹的偏好。通过利用 Nasonia 基因分型微阵列，我们已经确定了导入的区域是染色体 4 上的 16 Mb，尽管需要更完整的分析来确定该属中宿主偏好的确切遗传结构。据我们所知，这是首次将一种寄生蜂的宿主偏好导入另一种寄生蜂，也是少数几个在物种之间导入行为基因的案例之一。
