Collaborative Research: PurSUiT: Phylogenomics and taxonomic revision of Rhopalodiales - diatoms with obligate cyanobacterial endosymbionts

合作研究：PurSUiT：Rhopalodiales - 具有专性蓝细菌内共生体的硅藻的系统基因组学和分类学修订

• 批准号: 2222945
• 负责人: Scott Miller
• 金额: $ 31.7万
• 依托单位: University of Montana
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2222945&HistoricalAwards=false
• 关键词: Collaborative; Research; PurSUiT; Phylogenomics; taxonomic

Symbiosis, the close association of distinct organisms living together, is a common phenomenon in nature. From the ancient organelles inside human cells, to lichens and corals, the integration of life forms from disparate backgrounds occurs across the tree of life. What are the mechanisms that drive this integration to happen? What are the costs and benefits of these relationships? In one group of eukaryotic microorganisms called diatoms (which form the base of the food chain in aquatic ecosystems and generate more oxygen by photosynthesis than all rainforests combined), symbioses are commonly formed with cyanobacteria that “fix” nitrogen. This project will analyze how these organisms came together; whether that happened once or many times; the impacts of the association on host, symbiont and the ecosystems in which they live; and how the co-occurring organisms coordinate their life activities. Over 40 students will be involved in the research through courses, workshops, and research training. The project will be featured in the Hidden World of Microbial Diversity course offered through the University of Montana’s Indigenous Research and STEM Education summer program.A scientific collaboration between three U.S. universities and seven universities, research institutes and museums in China, India, Indonesia and Argentina will gather data from a variety of sources, including entire genomes of the chloroplast and mitochondria of the diatom hosts, cell wall morphology of the diatoms, and the entire genome of the cyanobacterial symbiont (also called a spheroid body) to address three main aims: 1) the evolutionary origins and diversification of the diatom order Rhopalodiales, including when the endosymbiont was acquired during diversification of this lineage; 2) the sister taxon of the Rhopalodiales, and the extent of cryptic diversity among cosmopolitan rhopalodian taxa; 3) the coevolution of host and symbiont. The project will integrate information on the group from herbarium collections in the United States, Europe and South America for both extant and fossil taxa. Integrated phylogenetics, functional genomics and taxonomic revisionary work will produce a time-calibrated phylogeny that will inform a revised classification system for the group.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.

共生是指生活在一起的不同生物的密切联系，是自然界的一种普遍现象。从人类细胞内的古老细胞器，到地衣和珊瑚，来自不同背景的生命形式的整合发生在生命之树上。驱动这种集成发生的机制是什么？这些关系的成本和收益是什么？在一种叫做硅藻的真核微生物中（硅藻是水生生态系统食物链的基础，通过光合作用产生的氧气比所有雨林加起来还多），通常与“固定”氮的蓝藻形成共生关系。这个项目将分析这些生物是如何聚集在一起的；不管这种事发生过一次还是多次；结合力对寄主、共生体及其所处生态系统的影响；以及共生生物如何协调它们的生命活动。40多名学生将通过课程、研讨会和研究培训参与研究。该项目将成为蒙大拿大学土著研究和STEM教育暑期项目提供的微生物多样性隐藏世界课程的特色。美国三所大学与中国、印度、印度尼西亚和阿根廷的七所大学、研究机构和博物馆之间的科学合作将从各种来源收集数据，包括硅藻宿主叶绿体和线粒体的全基因组、硅藻细胞壁形态和蓝藻共生体（也称为球形体）的全基因组，以实现三个主要目标：1)硅藻目Rhopalodiales的进化起源和多样化，包括在该谱系多样化过程中获得内共生体的时间；2) Rhopalodiales的姐妹类群，以及世界分布的rhopalodian类群的隐多样性程度；3)寄主与共生体的共同进化。该项目将整合来自美国、欧洲和南美洲植物标本馆现存和化石分类群的资料。综合系统发育学、功能基因组学和分类学修订工作将产生一个时间校准的系统发育，这将为该群体的修订分类系统提供信息。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。