DISSERTATION RESEARCH: Genomic basis of desert adaptation in rodents

这项研究的重点是在三个啮齿动物谱系中对极端环境（沙漠生态系统的干旱）的全基因组适应。了解生物体适应环境的特征的进化历史一直是进化生物学的核心目标。该项目将有助于最近的医学，农业和学术研究，这些研究已经揭示了负责复杂适应性状的基因，并确定这些基因突变对小鼠和其他哺乳动物（包括人类）的影响。一个特别重要的问题是“遗传工具箱”的范围是什么：对于一个共同的进化问题，比如在极端环境中茁壮成长，有多少进化上可行的解决方案？这个项目可能会进一步加深我们对分子水平上的趋同性和进化的可重复性的理解。此外，研究人员将与来自代表性不足的群体的本科生进行研究，并为该项目提供公共和K12外展服务。超高效肾脏通常与沙漠啮齿动物有关，这些啮齿动物几乎不喝免费水。这项研究探讨了这种特征的三个独立进化起源的遗传基础。 将对三对物种的转录组进行测序，一对是沙漠适应的，一对是温带适应的，并且将比较序列和表达数据以回答：1）在沙漠分类群中是否存在在温带分类群中看不到的氨基酸水平上的趋同？2)在某些或全部沙漠类群中，相同的基因是否处于选择之下？3)在沙漠类群中是否存在温带类群所没有的趋同基因表达模式？这项研究的结果将为生物体适应环境的方式以及基因组如何进化提供重要的见解。

The proposed study focuses on genome-wide adaptation to an extreme environment, the aridity of desert ecosystems, across three rodent lineages. Understanding the evolutionary history of traits that allow organisms to adapt to their environments has long been a central goal of evolutionary biology. The project will contribute to recent medical, agricultural, and academic research that has been uncovering the genes responsible for complex adaptive traits and determining the effect mutations in these genes have on mice and other mammals, including humans. An especially important question is what is the extent of the "genetic toolbox": how many evolutionarily viable solutions are there to a common evolutionary problem, like thriving in an extreme environment? This project potentially will further our understanding of convergence at the molecular level and the repeatability of evolution. In addition, the investigators will engage in research with undergraduates from underrepresented groups and provide public and K12 outreach on this project.Ultra-efficient kidneys are often associated with desert rodents who drink little to no free water. This study explores the genetic basis of three independent evolutionary origins of this trait. Transcriptomes will be sequenced for three pairs of species, one desert adapted and one temperate adapted, and sequence and expression data will be compared to answer: 1) is there convergence at the amino acid level in desert taxa not seen in the temperate taxa? 2) Are the same genes under selection in some or all of desert taxa? 3) Are there convergent gene expression patterns in the desert taxa not seen in the temperate taxa? The results from this research will provide essential insight into the way organisms adapt to their environment and how genomes evolve.