Dimensions US-China: Global Patterns of Biodiversity in the Ancient Ciliate Paramecium

中美：古代纤毛虫草履虫生物多样性的全球模式

• 批准号: 1927159
• 负责人: Michael Lynch
• 金额: $ 200万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1927159&HistoricalAwards=false
• 关键词: Dimensions; US; China; Global; Patterns; Dimensions; US; China; Global; Patterns

Do microbes exhibit patterns of biogeographic distribution similar to those of multicellular species? One idea is the 'everything is everywhere' hypothesis, which postulates high levels of migration scattering microbial species throughout the globe. Alternatively, environmental factors could be subdividing lineages into locally adapted taxa. This study focuses on a charismatic but poorly studied genus, the ciliate Paramecium, which originated prior to the appearance of vertebrates. These creatures are animal-like in many ways, such as having separate germline and somatic genomes and carrying a bacterial microbiome. Unlike animals, however, all species in this groups are similar in morphology, which simplifies many analyses. The population-genomic studies will reveal the extent to which intra- and interspecific variation is shaped by the population subdivision and migration. The researchers will explore the role of the microbiome in driving phylogenetic and geographic divergence. The study will examine if morphologically cryptic species are also similar in ecological/physiological traits. The combined efforts of two major ciliate labs, one in the US and one in China, will yield a public database of global molecular diversity. Graduate students and postdoctoral fellows will be trained by this research. Overall, this study will provide a wide-ranging exploration of speciation and adaptation in microbes of broad interest to the research community. An understanding of the distribution of biodiversity and its relevance requires information on key population-genetic parameters such as the power of random genetic drift and migration. Combined, these can constrain the development of local adaptations. This study will acquire whole-genome sequences in a worldwide survey of genetic variation within and among populations of 30 Paramecium species and their endocytobionts. Methods from molecular population genetics will yield estimates of global effective population sizes and migration rates for all such species. The temporal and geographic distributions of species will be revealed, and the existence of cryptic species complexes formally established. Classical methods from microbial physiology will estimate key parameters of basal metabolic requirements, growth, and cell size across gradients of temperature and resource availability. This work will be done on a wide range of geographic isolates of all species to determine whether local adaptation has occurred, or if such patterns are consistent with phenotypic-plasticity responses. Study of genotypes with and without endocytobionts will clarify whether such bacteria impose net metabolic losses or gains for their host cells. The resultant data will be organized into web portals to provide users with accessible assemblies and annotations of the genomes of all species, along with the survey of within-species variants found at all genetic loci. Sequenced strains will be cryopreserved in a viable state for use by future researchers.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.

微生物表现出与多细胞物种相似的生物地理分布模式吗？一个想法是“一切无处不在”的假设，它假设了在全球范围内的微生物物种的高水平迁移散射。另外，环境因素可能将谱系细分为本地适应的分类单元。这项研究的重点是具有魅力但研究良好的属纤毛映射的属，该属起源于脊椎动物出现之前。这些生物在许多方面都像动物一样，例如具有单独的种系和体细胞基因组和携带细菌微生物组。但是，与动物不同，该组中的所有物种在形态学上都是相似的，这简化了许多分析。人口基因组研究将揭示种群细分和迁移塑造的内部和种间变异的程度。研究人员将探索微生物组在驱动系统发育和地理差异中的作用。该研究将检查形态神秘的物种在生态/生理特征中是否也相似。两个主要的纤毛实验室的综合努力，一个在美国，一个在中国，将产生一个全球分子多样性的公共数据库。这项研究将接受研究生和博士后研究员的培训。总体而言，这项研究将为研究界广泛关注的微生物的物种形成和适应提供广泛的探索。 了解生物多样性及其相关性需要有关关键种群遗传参数的信息，例如随机遗传漂移和迁移的力量。结合在一起，这些可以限制局部适应的发展。这项研究将在全球范围内对30种西carparecium物种及其内吞to的遗传变异的全球遗传变异调查中获取全基因组序列。分子种群遗传学的方法将对所有此类物种的全球有效人口规模和迁移率产生估计。将揭示物种的时间和地理分布，并正式确定隐性物种复合物的存在。来自微生物生理的经典方法将估计温度和资源可用性梯度跨基础代谢需求，生长和细胞大小的关键参数。这项工作将在所有物种的广泛地理分离株上完成，以确定是否发生了局部适应性，或者这种模式是否与表型塑性响应一致。研究有或没有内吞to的基因型将阐明这种细菌是否施加净代谢损失或宿主细胞的增长。所得数据将被组织到Web门户网站，以向用户提供所有物种基因组的无障碍组件和注释，以及对所有遗传基因座的物种内部变体的调查。测序的菌株将在可行的状态下进行冷冻保存，以供未来的研究人员使用。该奖项反映了NSF的法定任务，并且使用基金会的知识分子优点和更广泛的影响评估标准，被认为值得通过评估来获得支持。