Paralogous VDRs in Teleosts: Transition of Nuclear Receptor Function Through Sub- and Neofunctionalization

鱼类由大约24,000个现存物种组成，是最多样化和最成功的脊椎动物群体之一。这些生物代表了广泛的生物学特征，并保持着相当大的遗传多样性。看来，这些生物的复杂性很大程度上是连续几轮基因复制的结果，导致许多重要基因的多个副本。多个基因拷贝的存在被认为对鱼类的进化及其多样性产生了很大影响。在鱼类中保留多个基因为深入了解基因如何通过特定过程进化提供了机会。这项研究将检验大多数鱼类中存在的多个维生素D受体基因(VDR)是否在复制后进化出新的功能和/或分割了祖先的功能。通过三个特定的目标，关键的维生素D受体结构-功能动力学，VDR基因表达的时空模式，以及维生素D受体在胚胎发育中的作用将被研究。建议的方法提供了系统和全面的调查，使详细评估维生素D受体的功能变化在一些进化的不同鱼类物种。这项工作的结果将通过加强保留、丢失或多样化基因副本如何有助于这些物种的内分泌创新的概念框架，支持对鱼类内分泌学进化的科学理解。作为这项研究计划的一部分，对本科生和研究生的培训将为教育和吸引年轻科学家提供独特的机会。除了每年的培训，学生们还将参加缅因州荒漠岛生物实验室(MDBL)的暑期研究项目。MDIBL设施长期致力于本科教育，重点是在各种水生动物中探索涉及海洋和淡水生物学的及时问题。

Fishes comprise approximately 24,000 existing species and are among the most diverse and successful groups of vertebrates. These organisms represent an extensive array of biological characteristics and maintain considerable genetic diversity. It appears that much of the complexity of these organisms is a result of successive rounds of genetic duplications resulting in multiple copies of many important genes. The presence of multiple gene copies is believed to have had a large impact on the evolution of fish and their diversity. The retention of multiple genes in fish provides the opportunity to gain insights into how genes evolve through specific processes. This research will examine whether multiple vitamin D receptor genes (VDRs) present in most fish species have evolved new functions and/or partitioned ancestral functions subsequent to duplication. Through three specific aims, critical vitamin D receptor structure-function dynamics, spatial-temporal patterns of VDR gene expression, and role of vitamin D receptor during embryo development will be investigated. The proposed approach provides a systematic and comprehensive investigation that enables a detailed evaluation of functional change of the vitamin D receptor across a number of evolutionary diverse fish species. Results of this work will support a scientific understanding of the evolution of fish endocrinology by enhancing the conceptual framework of how retention, loss or diversification of gene duplicates contributes to endocrine innovation in these species. Training of undergraduate and graduate students as part of this research plan will provide a unique opportunity to educate and engage young scientists. In addition to yearly training, students will participate in the summer research program at the Mount Desert Island Biological laboratory (MDBL) in Maine. The MDIBL facility has a long-standing dedication to undergraduate education with an emphasis on the exploration of timely questions involving marine and freshwater biology in a diverse array of aquatic fauna.