Genetic and functional analysis of eye degeneration in natural populations of a cave-dwelling crustacean

摘要： 了解眼睛的发育是理解正常功能的必要条件。 眼睛、再生能力和疾病的发展基础。多模型 系统，脊椎动物和无脊椎动物，历史上提供了许多重要的 关于眼睛形成的发育和遗传基础的数据。然而，障碍 存在在模型系统中研究眼睛发育的方法， 屏幕和眼睛大小自然发生的最小变化量。一个新颖 方法允许更好地了解发育和遗传基础 眼睛的形成是检查自然发生的眼睛大小的变化， 生物体，如洞穴动物中发生的。我们以前的工作表明， 使用非模式生物来模拟人类疾病的效用，当我们发现， 在人类白化病病例中，一种常见的突变基因也是导致白化病的原因 墨西哥丽脂鲤 我们最初选择了等足类甲壳动物Asellus aquaticus作为研究眼睛的模型 由于洞穴和地表之间眼睛大小的巨大差异而产生的变化 居住人口。我们随后对该物种的研究进一步证明了 优点包括在一个或多个眼内的多个独立的眼睛减少/损失机制。 单一洞穴种群，不同洞穴间眼睛丧失多种机制 人口，以及影响眼睛大小的大遗传成分。我们已经 产生了许多分子，发展和遗传工具和试剂， 帮助研究这个有趣的物种。我们的建议旨在了解遗传学 眼睛退化的原因首先，我们使用比较转录组 洞穴和表面胚胎样本测序作为一种无偏的方法，以确定 基因和途径负责眼睛退化的洞穴形式。二是 对杂交胚胎的转录组进行测序，以鉴定显示等位基因特异性的基因， 表达，并且puplatin含有顺式调节变化。接下来，我们验证基因 使用连接和功能技术从转录组测序中发现。 我们的工作为眼睛的发育和遗传基础提供了新的视角 大小差异，促进了A.水生物作为一个重要的模型， 眼睛退化和疾病。

Abstract: An understanding of eye development is necessary to comprehend proper functioning of the eye, capacity for regeneration, and the developmental basis of disease. Many model systems, both vertebrate and invertebrate, have historically provided much important data about the developmental and genetic basis of eye formation. However, hurdles exist studying eye development in model systems such as inherent biases in mutant screens and the minimal amount of naturally occurring variation in eye size. One novel approach allowing for a greater understanding of the developmental and genetic bases of eye formation is to examine naturally occurring eye size variation in non-model organisms, such as that occurs in cave animals. Our previous work demonstrated the utility of using non-model organisms to model human disease when we found that a commonly mutated gene in cases of human albinism was also responsible for albinism in the cavefish, Astyanax mexicanus. We initially chose the isopod crustacean, Asellus aquaticus as a model for studying eye variation because of the extreme difference in eye size between cave and surface dwelling populations. Our subsequent work on the species demonstrated further advantages including multiple independent mechanisms of eye reduction/ loss within a single cave population, multiple mechanisms of eye loss between different cave populations, and the large genetic component influencing eye size. We have already generated many molecular, developmental, and genetic tools and reagents that will assist in studying this interesting species. Our proposal aims to understand the genetics behind eye degeneration in this species. First, we use comparative transcriptome sequencing of cave and surface embryonic samples as an unbiased method to identify genes and pathways responsible for eye degeneration in the cave form. Second, we sequence transcriptomes of hybrid embryos to identify genes that show allele specific expression and that putatively contain cis-regulatory changes. Next, we validate genes discovered from the transcriptome sequencing using linkage and functional techniques. Our work provides a novel perspective on the developmental and genetic basis of eye size differences and furthers the development of A. aquaticus as an important model for eye degeneration and disease.