The Physiological Genomics of Diet Switching in Mammalian Herbivores

哺乳动物草食动物饮食转换的生理基因组学

• 批准号: 1656497
• 负责人: Michael Shapiro
• 金额: $ 76.57万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-05-01 至 2023-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1656497&HistoricalAwards=false
• 关键词: Physiological; Genomics; Diet; Switching; Mammalian

At every meal, animals that feed on plants (herbivores) such as deer, cattle, and rabbits, face the possibility of being poisoned by naturally-occurring toxic chemicals in their food. Nevertheless, how herbivores process natural toxins remains poorly understood. For example, remarkably little is known about the specific genes that control an animal's ability to process potentially toxic compounds in plants. To address these fundamental problems, this research will focus on a dramatic dietary change: woodrats normally eat juniper and cactus, but several populations in the American southwest have switched to a diet of creosote bush. Creosote bush produces natural toxins that radically differ from juniper and cactus, and therefore the specialized woodrat populations must detoxify their diets differently than the juniper and cactus-eaters. The goal of this project is to identify DNA-level changes that are associated with woodrats' ability to feed on a toxic diet of creosote bush. This project will develop new genomic tools that will be useful to the broader scientific community. A better understanding of how animals process toxins can also impact decisions about pharmaceutical development for humans and other animals, and influence feeding options to improve production of free-ranging domestic herbivores like cattle. Results of this work will be communicated to the public through an interactive display about the ecology of woodrats at the Utah Museum of Natural History. Despite decades of pharmacological research on model species and humans, the mechanisms used by mammalian herbivores to metabolize plant secondary compounds and the genomic basis underlying adaptation to new diets remain poorly understood. This research will investigate the evolution of dietary adaptation and specialization in mammalian herbivores by capitalizing on a dramatic diet change event: the replacement of juniper (Juniperus spp.) and cactus (Opuntia spp.) with creosote bush (Larrea tridentata) in the diets of herbivorous woodrats. The project has three goals: 1) Identify genomic changes associated with a radical dietary shift in Neotoma lepida. 2) Test for the repeated involvement of similar genetic pathways for specialization on creosote diets in N. bryanti. 3) Characterize the transcriptomic response of parental and hybrid populations of N. lepida and N. bryanti to a creosote diet. The proposed work leverages modern evolutionary genomic approaches to address a long-standing question in physiological ecology: which mechanisms are important in the processing of toxic diets? The project will lead to a deeper understanding of the responses of organisms to changes in the environment, including fundamental information at the genomic level about how mammalian herbivores adapt to dietary toxins. The project specifically tests whether the same genomic regions are under selection in two species that independently evolved the ability to specialize on creosote diets. An interactive display about the ecology of woodrats and their importance to society will be developed in collaboration with the Utah Museum of Natural History. Genomic tools will be developed that will be useful to the broader scientific community. In addition, the PIs will mentor students (high school through graduate) and postdocs in physiological genomics research on non-model species.

每顿饭，都以鹿，牛和兔子等植物（食草动物）为食的动物面临着被自然毒性的有毒化学物质中毒的可能性。 然而，食草动物如何处理天然毒素仍然知之甚少。例如，对于控制动物处理植物中潜在有毒化合物的能力的特定基因知之甚少。为了解决这些基本问题，这项研究将集中于急剧的饮食变化：伍德拉特人通常会吃杜松和仙人掌，但是美国西南部的几个人口已经转向了克里奥索斯灌木丛的饮食。杂糖灌木丛产生与杜松和仙人掌根本不同的天然毒素，因此，专业的伍德拉特种群必须对饮食排毒的饮食与杜松和仙人掌 - 食物的排毒不同。该项目的目的是确定与伍德拉斯（Woodrats）以杂糖灌木饮食为食相关的DNA级变化。该项目将开发新的基因组工具，这些工具将对更广泛的科学界有用。更好地了解动物如何处理毒素也会影响有关人类和其他动物药物开发的决策，并影响喂养方案，以改善自由放养的家用草食动物（如牛）的生产。这项工作的结果将通过犹他州自然历史博物馆的互动式展示传达给公众。 尽管对模型物种和人类进行了数十年的药理研究，但哺乳动物草食动物使用的机制代谢植物的次要化合物以及对新饮食的基因组基础适应性的理解仍然很差。这项研究将通过利用戏剧性的饮食变化事件来调查哺乳动物草食动物的饮食适应和专业化的演变：杜松（Juniperus spp。）和仙人掌（opuntia spp。）用Creosote Bush（larrea tridentata）在赫生木制的饮食中使用creosote Bush（larrea tridentata）。该项目有三个目标：1）确定与新瘤新瘤的根本性饮食转移相关的基因组变化。 2）测试在北乳杆菌中反复参与相似的遗传途径以专业化杂酚油饮食。 3）表征了Lepida和N. Bryanti的父母和杂种种群对杂糖饮食的转录组反应。提出的工作利用现代进化基因组方法来解决生理生态学长期存在的问题：哪些机制对于加工有毒饮食很重要？该项目将使对生物对环境变化的反应有更深入的了解，包括有关哺乳动物食草动物如何适应饮食毒素的基因组水平的基本信息。该项目专门测试了在两个独立进化出专门研究杂酚油饮食能力的两个物种中，相同的基因组区域是否正在选择。关于伍德拉斯生态及其对社会的重要性的互动展示将与犹他州自然历史博物馆合作发展。将开发基因组工具对更广泛的科学界有用。此外，PIS将指导学生（通过研究生高中）和博士后对非模型物种的生理基因组学研究。

项目成果

Successes and limitations of quantitative diet metabarcoding in a small, herbivorous mammal

小型草食哺乳动物定量饮食元条形码的成功和局限性

• DOI: 10.1111/1755-0998.13643
• 发表时间: 2022
• 期刊: Molecular Ecology Resources
• 影响因子: 7.7
• 作者: Stapleton, Tess E.;Weinstein, Sara B.;Greenhalgh, Robert;Dearing, M. Denise
• 通讯作者: Dearing, M. Denise

Wild herbivorous mammals (genus Neotoma) host a diverse but transient assemblage of fungi

• DOI: 10.1007/s13199-022-00853-0
• 发表时间: 2022-05
• 期刊: Symbiosis
• 影响因子: 2.5
• 作者: S. Weinstein;W. Stephens;R. Greenhalgh;J. Round;M. Dearing