Collaborative Research: EAGER: Non-Lethal Tools to Estimate the Ages and Lifespans of Chondrichthyan Fishes

本项目开发利用DNA测序技术研究衰老软骨鱼（如鲨鱼、鳐鱼和鳐鱼）的新方法。在这样做的过程中，它将促进这些物种的保护，其中许多是极度濒危的，以及我们对具有高度可变寿命和生活史的分类群体中物种衰老过程的进化理解。生物老化是生物体生命的基本组成部分。我们对衰老过程中DNA变化的理解的最新进展，为探索基因组变异性、生态动力学和生物体寿命之间的联系提供了新的工具。在所有脊椎动物的生命周期中，这些变化，当与已知年龄的动物进行校准时，可以用来创建高度精确的“时钟”。这样的时钟有可能为确定受保护物种的老龄化提供非致命的方法，并且对具有不同寿命的相关物种的衰老进行比较研究可能会为生命史进化的机制提供见解。此外，该项目将为本科生和博士后学者提供培训，并通过与乔治亚水族馆的合作，吸引普通和当地公众。生命系统的循环经历了以起始、生长和发育、繁殖、衰老和死亡为特征的生命史阶段。大多数关于生命史模式的进化驱动的假设都围绕着这样一个观点，即周期性的重置与缓慢但持续的新突变的引入相结合，通过重组（例如有性生殖）增强，提供了确保在不断变化的环境中生存所必需的表型变异性。如果这是正确的，那么在快速变化的环境中，循环时间应该比在更恒定的环境中要短。该项目将开发一种表观遗传DNA甲基化“时钟”，使用新颖的分子和计算方法来测量寿命和生活史差异很大的软骨鱼的寿命，这些鱼类居住的环境范围从相对稳定的深海到温带和热带地区海洋表面的高度动态环境。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。

This project develop new methods for aging chondrichthyans (e.g., sharks, skates, and rays) using DNA sequencing technology. In doing so, it will advance both the conservation of these species, many of which are critically endangered, and our evolutionary understanding of the aging process across species in taxonomic groups with highly variable lifespans and life histories. Biological aging is a fundamental component of organismal life. Recent advances in our understanding of changes in DNA during aging are yielding novel tools to probe the linkages between genomic variability, ecological dynamics, and organismal lifespans. These changes over the lifespan of all vertebrates, when calibrated against animals of known age, can be used to create highly accurate “clocks.” Such clocks have the potential to provide non-lethal approaches for determining aging populations of species of conservation concern, and comparative studies of aging across related species with diverse lifespans are likely to provide insight into the mechanisms contributing to life history evolution. In addition, the project will provide training for both undergraduates and a postdoctoral scholar and engage the general and local public through association with the Georgia Aquarium.Living systems cycle through life-history stages characterized by initiation, growth and development, reproduction, senescence, and death. Most hypotheses of the evolutionary drivers of life-history patterns center around the idea that periodic resetting in conjunction with the slow, but constant, introduction of new mutations augmented by reshuffling (e.g., sexual reproduction), provides the phenotypic variability necessary to ensure survival in changing environments. If this is correct, cycling times should be shorter in rapidly changing environments than they are in more constant environments. This project will develop an epigenetic DNA methylation “clock” using novel molecular and computational approaches to measure life spans in chondrichthyan fishes that vary widely in their lifespans and life histories and that inhabit environments that range from the relative constancy of the deep sea to highly dynamic environments at the sea surface in temperate and tropical regions.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.