Evolution of Parasite Specialization Across an Ancient Agricultural System

古代农业系统中寄生虫专业化的演变

• 批准号: 1754595
• 负责人: Nicole Gerardo
• 金额: $ 106.16万
• 依托单位: Emory University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-15 至 2023-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1754595&HistoricalAwards=false
• 关键词: Evolution; Parasite; Specialization; Across; Ancient

All parasites are specialists. This specialization is driven by the need for parasites to efficiently encounter and infect at least some hosts, which often comes at the cost of being able to infect others. At a broad-scale, parasite species adapt to a particular set of host species. At a finer-scale, many parasite strains specialize at overcoming the defenses of a narrow range of host genotypes within a species. There is little understanding of how evolutionary processes of host and parasite adaptation at the fine scale are linked to the evolution of parasite host ranges at broader scales, in part because few host-parasite systems are amenable to research at both scales. In this project the researchers will capitalize on a natural, ancient host-parasite system that allows for molecular investigation of parasite specialization at multiple scales. Escovopsis is a diverse genus of parasitic fungus that attacks other fungi cultivated by fungus-growing ants. Different Escovopsis species are able to infect different species of cultivated fungi, and at a finer scale, different Escovopsis genotypes are able to infect and utilize different host genotypes. Such parasite specificity suggests a dynamic pattern of adaptation and provides a rare opportunity to identify traits underlying parasite specialization at multiple scales. As part of this project, classes of undergraduate students will study parasite evolution through investigation of the parasites' host ranges and the parasites' genomes, and middle school students will learn about parasite evolution through an integrated science and art approach. Building on existing knowledge of Escovopsis diversity and host range, as well as recently gained insights into the Escovopsis genome, the researchers will couple experimental assays of parasite-host interactions, transcriptomics, population genomics and genetic manipulation to explore the genetic underpinnings of pathogen specialization. Specifically, the researchers will utilize transcriptomics and functional assays to identify the gene underlying the parasites' responses to host strains that they can and cannot infect. They will study the evolution of these genes in light of the evolution of the rest of the parasite genome through genomic comparisons across species and across strains within species. Taken together, the researchers will be able to assess whether similar traits underlie parasite specialization at broad and fine evolutionary scales in a tractable, ancient host-parasite system.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.

所有的寄生虫都是专家。这种专门化是由于寄生虫需要有效地遇到并感染至少一些宿主，而这往往是以能够感染其他宿主为代价的。在大范围内，寄生虫物种适应一组特定的宿主物种。在更精细的尺度上，许多寄生虫菌株专门克服一个物种内一小部分宿主基因型的防御。人们对宿主和寄生虫在精细尺度上的适应进化过程如何与更大尺度上的寄生虫宿主范围的进化联系在一起知之甚少，部分原因是很少有宿主-寄生虫系统适合在两个尺度上进行研究。在这个项目中，研究人员将利用一个自然的、古老的宿主-寄生虫系统，允许在多个尺度上对寄生虫专业化进行分子研究。Escovopsis是一种多样的寄生真菌属，它攻击由真菌生长的蚂蚁培养的其他真菌。不同的Escovopsis种类能够感染不同种类的栽培真菌，并且在更精细的尺度上，不同的Escovopsis基因型能够感染和利用不同的宿主基因型。这种寄生虫的特异性表明了一种动态的适应模式，并提供了在多个尺度上识别寄生虫特化特征的难得机会。作为该项目的一部分，本科生将通过调查寄生虫的宿主范围和寄生虫的基因组来研究寄生虫的进化，中学生将通过综合科学和艺术的方法来学习寄生虫的进化。基于对Escovopsis多样性和宿主范围的现有知识，以及最近对Escovopsis基因组的深入了解，研究人员将结合寄生虫-宿主相互作用的实验分析、转录组学、群体基因组学和遗传操作来探索病原体专业化的遗传基础。具体来说，研究人员将利用转录组学和功能分析来确定寄生虫对它们可以感染和不能感染的宿主菌株的反应背后的基因。他们将通过跨物种和物种内跨菌株的基因组比较，根据寄生虫基因组其余部分的进化来研究这些基因的进化。总之，研究人员将能够评估在一个易于处理的古老宿主-寄生虫系统中，相似的特征是否在广泛和精细的进化尺度上成为寄生虫专业化的基础。该奖项反映了美国国家科学基金会的法定使命，并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，被认为值得支持。

项目成果

Fungi inhabiting attine ant colonies: reassessment of the genus Escovopsis and description of Luteomyces and Sympodiorosea gens. nov.

• DOI: 10.1186/s43008-021-00078-8
• 发表时间: 2021-08-24
• 期刊: IMA fungus
• 影响因子: 5.4
• 作者: Montoya QV;Martiarena MJS;Bizarria R Jr;Gerardo NM;Rodrigues A
• 通讯作者: Rodrigues A