RoL: COLLABORATIVE RESEARCH: EXTREME ENVIRONMENTS, PHYSIOLOGICAL ADAPTATION, AND THE ORIGIN OF SPECIES

ROL：合作研究：极端环境、生理适应和物种起源

• 批准号: 2423844
• 负责人: Michael Tobler
• 金额: $ 78.31万
• 依托单位: University of Missouri-Saint Louis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-10-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2423844&HistoricalAwards=false
• 关键词: RoL; COLLABORATIVE; RESEARCH; EXTREME; ENVIRONMENTS

Extreme environments allow for the investigation of life's capacity and limitations to cope with far-from-average environmental conditions. Springs rich in hydrogen sulfide represent some of the most extreme freshwater environments because hydrogen sulfide halts energy production in animal cells. Nonetheless, some fish have colonized sulfide springs throughout the Americas and have evolved into new species in the process. This project will investigate how the genetic changes that mediate the fish's ability to tolerate hydrogen sulfide impact their ability to successfully interbreed with related fish that live in adjacent freshwater streams. It involves the identification of genetic differences between hydrogen sulfide-tolerant and susceptible populations, particularly in genes associated with pathways affected by hydrogen sulfide toxicity. In addition, it will be tested how hybrids between tolerant and susceptible populations differ from their parents. Specifically, the function of mitochondria and whole organisms will be compared between parents and hybrids in presence or absence of hydrogen sulfide. This project will yield new insights into how adaptation to environmental stress leads to genetic incompatibilities that represent barriers for interbreeding between populations, and thus, into how new species form. This project provides training opportunities in integrative biology for participants at all levels of higher education. It will also contribute to science education and public outreach by training scientists to become effective science communicators and reach non-expert audiences in collaboration with informal education institutions. Natural selection drives adaptive evolution and can cause speciation. However, the potential role of intrinsic genetic incompatibilities during speciation with gene flow remains largely unknown. Investigating speciation with gene flow in the context of physiological adaptation allows closing existing gaps of knowledge. This is possible through integrated analyses of how selection shapes genomic divergence, how recombination of divergent genomes in hybrids affects physiological function, and how these functional consequences affect the speciation process. This project tests a priori predictions about the links between physiological adaptation to toxic hydrogen sulfide and the emergence of reproductive isolation. It will focus on components of a highly conserved metabolic pathway, oxidative phosphorylation (OXPHOS), which plays a central role in adaptation to hydrogen sulfide. Because OXPHOS components are encoded by both the mitochondrial and the nuclear genomes, theory predicts that adaptive modification of OXPHOS should give rise to mitonuclear incompatibilities and contribute to the speciation process. This project investigates the mechanistic links between physiological adaptation and speciation by testing a priori predictions about (1) how OXPHOS adaptation affects genomic divergence between populations living in different environments, (2) the functional consequences of mitonuclear incompatibilities at the biochemical, physiological, and organismal levels, and (3) the relative role of mitonuclear incompatibilities during speciation. The project employs an integrative approach that combines population genomics, assays of enzyme, organelle, and whole organism function, as well as field and laboratory experiments for the quantification of multiple pre- and postzygotic mechanisms of reproductive isolation.This award was co-funded by BIO/Emerging Frontiers, DEB/Evolutionary Processes, and IOS/Integrative Ecological Physiology.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.

极端环境可以调查生活能力和局限性，以应对远离平均环境条件。富含硫化氢的弹簧代表了一些最极端的淡水环境，因为硫化氢会停止动物细胞的能量产生。尽管如此，一些鱼类在整个美洲都定殖了硫化物弹簧，并在此过程中发展成为新物种。该项目将研究如何介导鱼类耐硫化氢的能力的遗传变化会影响其成功与生活在相邻淡水流中的相关鱼类杂交的能力。它涉及鉴定硫化氢氢和易感人群之间的遗传差异，特别是在与受硫化氢毒性影响的途径相关的基因中。此外，它将测试宽容和易感人群之间的杂种与父母的不同。具体而言，在存在或不存在硫化氢的情况下，将比较父母和杂种之间的线粒体和整个生物的功能。该项目将对适应环境压力的适应导致遗传不相容性的新见解，这些遗传不兼容代表了种群之间杂交的障碍，从而涉及新物种的形成方式。该项目为各级高等教育的参与者提供了综合生物学的培训机会。这也将通过培训科学家通过培训科学家成为有效的科学沟通者并与非正式教育机构合作吸引非专业的受众群体来为科学教育和公众推广做出贡献。自然选择驱动自适应演变并可能导致物种形成。然而，内在遗传不相容性在与基因流相形成过程中的潜在作用在很大程度上仍然未知。在生理适应的背景下，研究基因流的物种流程可以缩小现有的知识差距。通过综合分析选择了选择如何塑造基因组差异，杂种中差异基因组的重组如何影响生理功能，以及这些功能后果如何影响物种形成过程。该项目测试了关于生理适应硫化物与生殖分离的出现之间的联系的先验预测。它将集中于高度保守的代谢途径，氧化磷酸化（OXPHOS）的成分，该途径在适应硫化氢中起着核心作用。由于Oxphos成分是由线粒体和核基因组编码的，因此理论预测，Oxphos的自适应修饰应引起线核的不相容性，并有助于物种形成过程。该项目通过测试（1）关于（1）Oxphos适应如何影响生活在不同环境中的人群之间的基因组差异的先验预测，研究生理适应和物种形成之间的机理联系，（2）在生物化学，物理学，物理和生物体层面和（3）相对（3）的作用下，在生物化学，生物化学层面和（3）相对（MITIC）的作用。 The project employs an integrative approach that combines population genomics, assays of enzyme, organelle, and whole organism function, as well as field and laboratory experiments for the quantification of multiple pre- and postzygotic mechanisms of reproductive isolation.This award was co-funded by BIO/Emerging Frontiers, DEB/Evolutionary Processes, and IOS/Integrative Ecological Physiology.This award reflects NSF's法定任务，并被认为是值得通过基金会的智力优点和更广泛影响的审查标准来评估的值得支持的。