Co-evolution of the Opioid/Orphanin Gene Family and Cognate Receptor Gene Families

阿片类/孤啡肽基因家族和同源受体基因家族的共同进化。PI：Robert M.多雷斯丹佛大学University of Denver 器官系统之间的通信是由两个细胞间的通信系统，神经系统和内分泌系统，促进整个身体的信息流动。在这些通信网络中，关键信息由化学信号（配体）携带，这些化学信号以高度选择性的方式与靶细胞上的特定受体相互作用，这是一种“锁和钥匙”策略。这些配体/受体相互作用的起源是未知的，但本提案中的研究将检查来自古老谱系的物种，以重建在不同化学通讯网络的进化过程中发生在配体编码和受体编码基因中的转化。为了研究配体编码基因及其相应受体编码基因的协同进化，本研究拟利用配体编码基因家族（阿片和黑皮质素配体的来源）中的阿片/阿片受体、阿片受体编码基因家族和黑皮质素受体基因家族，这三个基因家族提供了很好的模型。阿片样物质/黑素配体影响镇痛、心血管功能和免疫系统的一些作用，而黑皮质素参与慢性应激调节、脂肪和葡萄糖代谢以及进食行为。学生将分析脊椎动物辐射中关键分支点的物种，例如：肺鱼，Neoceratodus forsteri，白色鲟鱼，Acipenser transmontanus，角鲨，Heterodontus francisci，鼠鱼，Hydrolagus colliei，以及无颌脊椎动物，Myxine spectorosa（八目鳗）和Petromyzon marinus（七鳃鳗）。研究将整合这些物种中配体编码基因的克隆及其各自同源受体编码基因的克隆。克隆的受体将在细胞系中表达，用于结合研究分析，并确定这些受体在中枢神经系统和外周组织中的分布。这些研究将揭示这些项目所选物种中配体和受体的新序列。将创建受体序列和配体序列数据库，以鉴定在未来定点诱变实验中可以修饰的氨基酸基序，以解决结构/功能相关问题。这些研究可能导致开发可能具有治疗应用的配体（阿片类药物和黑皮质素）类似物。项目将由博士进行。以及硕士研究生和本科荣誉生。少数民族学生将被招募为夏季REU（NSF本科生研究经验）职位。最后，与这一系列研究相关的分子克隆项目将被纳入每年的实验室技术课程BIOL 3655“分子神经内分泌学”。该建议适合生物系统信息学领域，其中基因组进化的问题可以使用基因组序列数据库分析来解决。 该提案将为大型配体/受体序列数据库添加信息，并对数据库进行“数据挖掘”，以获得对受体/配体蛋白质进化和相关基因共同进化的新见解。

Title:Co-evolution of the Opioid/Orphanin Gene Family and Cognate Receptor Gene Families. PI: Robert M. Dores. Institution : University of Denver Communication among organ systems is accomplished by two intercellular communication systems, the nervous system and the endocrine system, that facilitates the flow of information throughout the body. In these communication networks, critical messages are carried by chemical signals (ligands) that interact in a highly selective manner with specific receptors on a target cell, a "lock and key" strategy. The origin of these ligand/receptor interactions are unknown, but the studies in this proposal will examine species from old lineages in order to reconstruct the transformations that have occurred in ligand-coding and receptor-coding genes during the evolution of distinct chemical communication networks. In order to study the co-evolution of ligand-coding genes and their corresponding receptor-coding genes this proposal will use the opioid/orphanin ligand-coding gene family (the source of opioid and melanocortin ligands), the opioid receptor-coding gene family and the melanocortin receptor gene family, which provide excellent models. The opioid/orphanin ligands influence analgesia, cardiovascular function, and some actions of the immune system, while the melanocortins are involved in chronic stress regulation, fat and glucose metabolism, and feeding behavior. Students will analyze species at critical branch points in the radiation of vertebrates such as: the lungfish, Neoceratodus forsteri, the white sturgeon, Acipenser transmontanus, the horn shark, Heterodontus francisci , the ratfish, Hydrolagus colliei, and the jawless vertebrates, Myxine glutinosa (hagfish) and Petromyzon marinus (lamprey). Studies will integrate the cloning of ligand coding genes with the cloning of their respective cognate receptor-coding genes in these species. The cloned receptors will be expressed in cell lines for binding study analysis, and the distribution of these receptors in the central nervous system and in peripheral tissues will be determined. These studies will reveal novel sequences for both ligands and receptors in the species that have been selected for these projects. Receptor sequence and ligand sequence databases will be created to identify amino acid motifs that could be modified in future site directed mutagenesis experiments to address structure/function related questions. These studies may lead to the development of analogs to the ligands (opioids and melanocortins) that may have therapeutic applications. Projects will be conducted by Ph.D. and MS graduate students and undergraduate honors students. Minority students will be recruited for summer REU (NSF Research Experience for Undergraduates) positions. Finally, a molecular cloning project related to this set of studies will be incorporated into the lab techniques course, BIOL 3655 "Molecular Neuroendocrinology" annually. This proposal fits into the area of Biological Systems Informatics in which questions of genome evolution can be addressed using genomic sequence database analyses. This proposal will both add information to a large ligand/receptor sequence database, as well as "data-mine" the database for new insights into receptor/ligand protein evolution and linked gene co-evolution.