Collaborative Research: Cestode phylogeny and genomics

绦虫是寄生虫，包括哺乳动物中具有医学和兽医重要性的许多物种以及寄生于基本上所有其他脊椎动物群的数千种物种。然而，我们对绦虫主要类群的进化知之甚少。这不仅阻碍了我们治疗绦虫感染的医疗和兽医重要性的能力，但它也限制了绦虫作为模型寄生虫系统的使用，以帮助扩大我们对食物网连接和生态系统健康的理解，并帮助告知渔业管理实践。该项目旨在生成所需的分子和形态学数据，以大大扩展我们对绦虫进化的理解。通过这样做，它将把绦虫及其脊椎动物宿主转变为全球最知名的宿主/寄生虫系统之一，使该系统充分发挥其潜力。为本科生，研究生和博士后研究人员提供的培训将使他们具备可转移的STEM技能。此外，将通过编制主要绦虫群的检索表、编制关于绦虫的儿童书籍的电子书版本以及利用现有的全球绦虫数据库，向所有年龄的不同受众在线公开提供关于绦虫的信息。最近的一项全球调查发现，鲨鱼和鳐寄生的绦虫谱系是绦虫纲多样化的核心。目前，这一级别共有19个订单。初步的系统发育研究表明，目前的顺序分类的类大大低估了谱系的多样性，特别是在组的板鳃类宿主绦虫。这项工作的目的是提供一个强大的寄生虫类的基础上有针对性的基因捕获的738个位点的960种绦虫。绦虫更高级别的分类将被修订，以反映单系群，通知新的形态和分子数据。20个物种的完整基因组的产生跨越了大约2亿年的差距之间的绦虫的医学和兽医的重要性，这些数据是目前可用的，将提供深入了解模式的分类特异性基因家族的进化绦虫。基因组分析的目的是利用海洋和非海洋栖息地之间的多个独立的过渡，板鳃类和非板鳃类的最终主机，无脊椎动物和脊椎动物的最终中间主机，已发生在进化时间，以确定签名的平行进化。这些特征有望为深入了解环境因素提供有价值的见解，这些环境因素可能在具有复杂生命周期的寄生虫系统的进化中发挥了作用。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

Tapeworms are parasites that include numerous species of medial and veterinary importance in mammals as well as thousands of species that parasitize essentially all other groups of vertebrate animals. Yet, we know little about the evolution of the major groups of tapeworms. Not only does this hamper our ability to treat tapeworm infections of medical and veterinary importance, but it also limits the use of tapeworms as model parasite systems to help expand our understanding of food web connections and ecosystem health, and to help inform fisheries management practices. This project aims to generate the molecular and morphological data required to substantially expand our understanding of the evolution of tapeworms. In doing so, it will transform tapeworms and their vertebrate hosts into one of the best known host/parasite systems globally, allowing this system to reach its full potential. The training provided to undergraduate, graduate and postdoctoral researchers will equip them with transferable STEM skills. Furthermore, information about tapeworms will be made publicly available on-line to diverse audiences of all ages by creating a key to the major tapeworm groups, developing an e-book version of a children's book on tapeworms, and building upon an existing global cestode database. A recent global survey has identified tapeworm lineages hosted by sharks and rays as central to the diversification of the Cestoda. This class currently comprises 19 orders. Preliminary phylogenetic work suggests that the current ordinal classification of the class substantially underestimates lineage diversity, especially within the groups of elasmobranch-hosted cestodes. The proposed work aims to provide a robust phylogeny of the class based on targeted gene capture of 738 loci for 960 species of tapeworms. Cestode higher-level classification will be revised to reflect monophyletic groups, informed by new morphological and molecular data. The generation of complete genomes for 20 species spanning the approximately 200-million year gap between the cestodes of medical and veterinary importance for which such data are currently available will provide insight into patterns of taxon-specific gene family evolution across cestodes. Genomic analyses have been designed to take advantage of the multiple independent transitions between marine and non-marine habitats, elasmobranch and non-elasmobranch definitive hosts, and invertebrate and vertebrate final intermediate hosts that have occurred over evolutionary time to identify signatures of parallel evolution. Such signatures are anticipated to provide valuable insight into environmental factors that may have played a role in the evolution of parasite systems with complex life cycles.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.