Collaborative Research: EAGER: Developing tools to assess the evolutionary implications of partial clonality in alpine snow algae

合作研究：EAGER：开发工具来评估高山雪藻部分克隆性的进化影响

• 批准号: 2113747
• 负责人: Robin Kodner
• 金额: $ 8.21万
• 依托单位: Western Washington University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2113747&HistoricalAwards=false
• 关键词: Collaborative; Research; EAGER; Developing; tools

Many globally important processes like carbon cycling and human disease dynamics are a result of microscopic eukaryotes. Yet our understanding of evolutionary processes across the entire tree of life is limited due to the inherent challenges of studying microscopic taxa. Tools developed for macroscopic, and often obligately sexually reproducing, species are often not tractable in microbes where generation times are short, population sizes large, and extracting DNA from individual cells difficult. Further, population-level ecology and evolutionary biology research have focused on species that can be grown in the lab; yet, only ~1% of microbes can be cultured. This proposal focuses on the snow algae, a group of closely related, single-celled algae that turn seasonal snow packs pink or red. The aim is to develop novel single-cell population genetic protocols to study these threatened organisms and sentinels of environmental change. Thousands of cells from inter- and intra-annual Chlainomonas-dominated blooms in the Cascade Range of the United States will be genotyped. A goal is to understand how environmental factors (e.g., nitrogen) influence snow algal reproduction. The project will support two graduate students. The three PIs will integrate data into classroom-based and field-based curriculum for university-level students and share data with the public through social media and peer-reviewed publications.This project uses snow algae to develop new methods for studying the population genetics of microbial eukaryotes from natural populations. The work will provide novel and critical techniques for studying reproductive modes that will be broadly applicable across microbial systems. Two novel elements are proposed: (1) combining single-cell isolation methods with state-of-the-art multilocus genotyping, and (2) using a novel microbial eukaryotic system (snow algae) with features making the method development tractable. Reproductive mode data will be generated and combined with measurements of (i) the ploidy of cells and (ii) environmental conditions to ascertain whether limited nitrogen initiates sexual reproduction. The approach is radically different compared to traditional microalgal population genetics that rely on lab-based cultures, raising questions of how representative those data are in nature. This proposal fits the EAGER funding mechanism as the single-cell population genetic methods are high risk-high payoff and should be readily transferable to other systems.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.

许多全球重要的过程，如碳循环和人类疾病动力学，都是微观真核生物的结果。然而，由于研究微观分类群的固有挑战，我们对整个生命之树的进化过程的理解是有限的。为宏观而开发的工具，通常是专性繁殖的，在繁殖时间短、种群规模大、从单个细胞中提取DNA困难的微生物中，物种往往不容易处理。此外，种群水平的生态学和进化生物学研究集中在可以在实验室中生长的物种上；然而，只有约1%的微生物可以被培养。这项提案的重点是雪藻，这是一组密切相关的单细胞藻类，可以将季节性积雪变成粉红色或红色。目的是开发新的单细胞群体遗传方案来研究这些受威胁的生物和环境变化的哨兵。美国喀斯喀特山脉以衣原体为主的年际和年内繁殖的数千个细胞将被基因分型。目标是了解环境因素（如氮）如何影响雪藻繁殖。该项目将资助两名研究生。这三个pi将把数据整合到面向大学水平学生的课堂和实地课程中，并通过社交媒体和同行评审出版物与公众分享数据。本项目利用雪藻开发新的方法，从自然种群中研究微生物真核生物的种群遗传学。这项工作将为研究生殖模式提供新的和关键的技术，这将广泛适用于整个微生物系统。提出了两个新元素：(1)将单细胞分离方法与最先进的多位点基因分型相结合；(2)使用一种新的真核微生物系统（雪藻），其特点使方法开发易于处理。将生成生殖模式数据，并将其与(i)细胞倍性和（ii）环境条件的测量相结合，以确定有限的氮是否会引发有性生殖。与传统的依靠实验室培养的微藻种群遗传学相比，这种方法截然不同，这就提出了这些数据在自然界中具有多大代表性的问题。由于单细胞群体遗传方法具有高风险和高收益的特点，并且易于转移到其他系统，因此该建议符合EAGER资助机制。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。