DISSERTATION RESEARCH: The evolutionary origin and genetics of color pattern diversity in Phyllobates poison frogs

论文研究：叶状毒蛙颜色图案多样性的进化起源和遗传学

• 批准号: 1702014
• 负责人: Marcus Kronforst
• 金额: $ 2.1万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-01 至 2019-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1702014&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; evolutionary; origin; genetics

This project will identify the genes responsible for color pattern variation between different Poison-dart frogs. These frogs are well known for their brightly colored patterns, which serve as warning signals to deter potential predators. Within one small group of Poison-dart frogs (Phyllobates), vivid bright yellow colorations have independently evolved multiple times from dark, striped ancestors; in one species, different color morphs even occur within the same population. The researchers will take advantage of new genomic technologies and statistical analyses to identify the genes that differ between striped and solid-colored frogs. Results will provide critical insights on the genetic processes that underlie the independent evolution of color pattern variants in this group of frogs. The research will also reveal important information on the spread of beneficial genetic mutations within and across populations. In addition, the project will provide research opportunities for undergraduate students. Planned outreach includes public seminars and educational activities for elementary and middle school children. To pinpoint the genetic elements responsible for convergent evolution across Phyllobates species, this project takes advantage of ontogenetic, interspecific, and intraspecific variation in color pattern. First there is striking variation in color pattern between two pairs of closely related Phyllobates lineages, and within a population of Phyllobates aurotaenia from the upper San Juan River in Colombia. The researchers will use exon enrichment and next-generation sequencing to find loci that are highly differentiated between striped and solid-colored lineages, and statistically associated with color pattern variation within P. aurotaenia. Second, gene expression during coloration development will be studied using RNAseq, in order to identify genes that are up or down-regulated when changes in coloration occur throughout development. These two approaches will yield a set of putative loci behind color pattern variation in Phyllobates. The researchers will then use a combination of molecular phylogenetics and coalescent simulations to infer the evolutionary history of these loci, in order to shed light on the genetic mechanisms behind the convergent evolution of bright yellow coloration in this group of frogs.

该项目将确定不同毒镖蛙之间颜色模式差异的基因。这些青蛙以其鲜艳的图案而闻名，这些图案可以作为警告信号来阻止潜在的捕食者。在一小群毒镖蛙（Phyllobates）中，鲜艳的亮黄色颜色已经从深色条纹祖先独立进化了多次;在一个物种中，不同的颜色变体甚至出现在同一种群中。研究人员将利用新的基因组技术和统计分析来确定条纹蛙和纯色蛙之间的差异基因。结果将提供关键的洞察力的遗传过程，在这组青蛙的颜色模式变异的独立进化的基础。这项研究还将揭示有益基因突变在人群内和人群间传播的重要信息。此外，该项目将为本科生提供研究机会。计划的推广活动包括为小学和中学儿童举办公共研讨会和教育活动。为了查明负责Phyllobates物种趋同进化的遗传因素，该项目利用了个体发育，种间和种内颜色模式的变化。首先，在两对密切相关的Phyllobates谱系之间，以及在哥伦比亚圣胡安河上游的Phyllobates aurotaenia种群中，颜色模式存在显著差异。研究人员将使用外显子富集和下一代测序来寻找在条纹和纯色谱系之间高度分化的基因座，并与P. aurotaenia内的颜色模式变异统计相关。其次，将使用RNAseq研究着色发育期间的基因表达，以鉴定在整个发育过程中发生着色变化时上调或下调的基因。这两种方法将产生一组假定的基因座背后的颜色模式的变化叶状。然后，研究人员将使用分子遗传学和结合模拟的组合来推断这些基因座的进化历史，以便揭示这组青蛙中亮黄色趋同进化背后的遗传机制。