Collaborative Proposal: Developmental and Genetic Pathways to Phenotypic Convergence in a Radiation of Groundwater Salamanders

合作提案：地下水蝾螈辐射表型趋同的发育和遗传途径

• 批准号: 2032633
• 负责人: Dana García
• 金额: $ 36.67万
• 依托单位: Texas State University - San Marcos
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2032633&HistoricalAwards=false
• 关键词: Collaborative; Proposal; Developmental; Genetic; Pathways

Cave organisms as unrelated as insects and salamanders often have shared features – such as lack of eyes, pallid coloration, and elongated limbs. Life underground provides different challenges from life on the surface, and those challenges favor relatively rapid changes in appearance (and other, more subtle characteristics) at the population level. Those rapid changes lead to convergence in the appearance of many cave organisms, but the genetic and developmental processes that lead to repeated changes in different organisms are largely unknown. The Edwards Plateau of central Texas has an extensive, though fragmented, network of springs, caves, and aquifers that host numerous, diverse, underground salamanders. These salamanders attain reproductive maturity while retaining features (such as gills) that are characteristic of immature salamanders, and many of them show eyes reduced in size and development to varying degrees, along with other characteristics associated with living underground (e.g. an enhanced sense of smell). These characteristics have evolved independently and repeatedly in the various species, and this research will integrate information derived through a variety of approaches to shed light on the mechanisms that enable new structures and functions to evolve. This project is timely because in addition to enhancing understanding of the evolution of sensory systems, it will highlight and clarify the diversity of salamanders in central Texas at a time when human population growth and commercial development further threaten species that have been identified as being in danger of extinction. Finally, this project will serve as a platform to train numerous undergraduates in STEM research.The researchers will use an integrative, hierarchical approach combining genetic, developmental, and phylogenetic perspectives to study the mechanisms that drive convergence in phenotypes of subterranean Groundwater Salamanders. Results from micro-computed tomography imaging, histology, transcriptomics, and exon sequencing will demonstrate the degree of morphological convergence in sensory systems (visual, olfactory, and lateral line) across subterranean lineages. Comparative transcriptomics will be employed to examine the developmental genetic mechanisms of organ system reduction and signatures of molecular convergence at the protein-coding level in sensory-system genes.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.

像昆虫和萨拉曼类人一样无关的洞穴生物通常具有共同的特征，例如缺乏眼睛，苍白的着色和伸长的四肢。 Life Underground提供了表面生活的不同挑战，这些挑战有利于人口一级的外观（以及其他更微妙的特征）的相对较快的变化。这些快速变化导致许多洞穴生物的出现，但是导致不同生物体反复变化的遗传和发育过程在很大程度上是未知的。德克萨斯州中部的爱德华兹高原拥有广泛但分散的弹簧，洞穴和含水层网络，可容纳众多，多样化的地下sal。这些Salamanders在保留未成熟sal的特征的特征（例如Gills）的同时，具有复制的成熟度，其中许多人的眼睛显示出大小和发育的不同程度，以及与生活在地下相关的其他特征（例如，增强的嗅觉感）。这些特征已经在各种物种中独立而反复演变，这项研究将通过各种方法来综合信息，以阐明使新的结构和功能进化的机制。该项目之所以及时，是因为除了增强对感官系统的发展的理解外，它将强调和阐明德克萨斯州中部的sal多样性在人口增长和商业发展进一步威胁到已被确定为处于延伸危险中的时候。最后，该项目将作为培训STEM研究中众多大学生的平台。研究人员将使用综合的，等级的方法结合遗传，发育和系统发育观点来研究驱动地下地下水sal剂表型中收敛的机制。微型计算的断层扫描成像，组织学，转录组学和外显子测序的结果将证明跨地下谱系中感觉系统（视觉，嗅觉和外侧线）中的形态收敛程度。将使用比较转录组学检查器官系统减少的发展遗传机制和在感觉系统基因中蛋白质编码水平上分子收敛的特征。该奖项反映了NSF的法定任务，并通过使用该基金会的智力功能和广泛的影响来评估Criteria criteria诚实地认为，通过评估诚实地将其视为诚实。