STRUCT/FUNCTIONAL GENOMICS OF OLFACTORY RECEPTOR GENES

嗅觉受体基因的结构/功能基因组学

• 批准号: 6176115
• 负责人: BARBARA J. TRASK
• 金额: $ 2.03万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-01 至 2000-09-27
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6176115
• 关键词: artificial chromosomes; chemoreceptors; fluorescent in situ hybridization; gene expression; genetic library; genetic mapping; genetically modified animals; genome; human genetic material tag; human subject; laboratory mouse; molecular cloning; nucleic acid sequence; olfactions; polymerase chain reaction; regulatory gene; respiratory epithelium; restriction fragment length polymorphism; southern blotting; structural genes

Our ability to smell thousands of different odors is mediated by a large repertoire of odorant receptors (OR) expressed on sensory neurons in the nose. The Ors bind odorous molecules and transmit this information to the brain. During development, Ors also guide neurons to spatially fixed relay stations in the olfactory bulb. Ors form one of the largest gene families in the mammalian genome, with at least 1000 members. OR genes are distributed on many chromosomes in clusters that may occupy as much as 1 percent of the genome. The family also includes many pseudogenes and OR- like genes that may perform other chemosensory functions, such as cell-cell recognition or sperm chemotaxis. This project s goal is to learn (A) how the diversity of the expressed repertoire of Ors has evolved to meet the differing demands for olfaction in mouse and human; (B) how transcription of these genes is controlled such that each sensory neuron expresses a single OR, while a diverse repertoire is displayed in the nose as a whole; (C) how the specificity of ligand-binding and neuronal-targeting is embodied in the structure of the OR proteins; (D) whether the complex genomic organization of Ors is based on functional considerations; (E) how the OR genes responsible for the sense of smell are distinguished from and organized relative to other members of the family; (F) how the evolutionary dynamic nature of the OR subgenome impacts the functional repertoire; and (G) how the repertoire varies among individuals or with age exposure to odors. We therefore propose to conduct a comprehensive and detailed genomic analysis of the OR families in mouse and human and to integrate these genomic data with assays of gene function and regulation. Aim 1 is to characterize nearly the full repertoire of Ors active in the olfactory tissue of mouse and human. Aim 2 is to map the locations of these active Ors and to sequence all OR-like sequences, including pseudogenes and ones functioning outside the nose, at each chromosomal location. Aim 3 is to characterize genomic sequence encompassing approximately 20 percent of the active OR genes to make paralogous and orthologous comparisons of gene structure and cluster organization. Aim 4 is to characterize the 5'UTRs and expression patterns of OR genes and to perform functional assays in mice to identify regulatory motifs and structural elements key for ligand-binding and neuron-targeting. Aim 5 is to develop technology to use cDNA arrays to examine expression profiles of 100's of OR genes at once. This partnership between the Axel group, with expertise in transgenics and olfactory biology, and the Trask and Hood groups, with experience in sequencing, genomic evolution, and cDNA-array technology, represents a unique opportunity to unite the worlds of large-scale genomics and functional biology. It is our belief that this sort of partnership in functional genomics represents a model for future collaborative efforts to characterize complex neurobiological systems and large gene families.

我们闻到数千种气味的能力是由在鼻子中的感觉神经元上表达的大量气味受体（OR）介导的。 ORS结合有臭的分子并将这些信息传输到大脑。 在开发过程中，ORS还引导神经元在嗅球中的空间固定继电器站。 ORS构成了哺乳动物基因组中最大的基因家族之一，至少有1000名成员。 或基因分布在簇中的许多染色体上，可能占基因组的1％。 该家族还包括许多可能执行其他化学感应功能的假基因和类似基因，例如细胞 - 细胞识别或精子趋化性。 该项目的目标是学习（a）ORS表达曲目的多样性如何发展以满足小鼠和人类对嗅觉的不同需求； （b）如何控制这些基因的转录，使每个感觉神经元表达单个或单一的曲目，而整个鼻子则显示出多种曲目； （c）如何在或蛋白质的结构中体现配体结合和神经元靶向的特异性； （d）ORS的复杂基因组组织是否基于功能考虑因素； （e）如何将负责嗅觉的或基因与家族的其他成员区分开并组织； （f）或亚基因组的进化动态性质如何影响功能库； （g）曲目如何在个体之间或随着气味的年龄暴露而变化。 因此，我们建议对小鼠和人类中的家族进行全面，详细的基因组分析，并将这些基因组数据与基因功能和调节的测定结合。 目的1是表征几乎活跃于小鼠和人类嗅觉组织中的ORS的完整曲目。 AIM 2是在每个染色体位置绘制这些活性ORS的位置，并测序所有类似或类似的序列，包括假基因和鼻子外部功能。 AIM 3是表征大约20％的活性或基因的基因组序列，以对基因结构和簇组织进行寄生和直系同源的比较。 目标4是表征或基因的5'UTR和表达模式，并在小鼠中执行功能测定，以鉴定调节基序和结构元素的配体结合和神经元靶向的关键。 AIM 5是开发使用cDNA阵列的技术，一次检查100或基因的表达曲线。 Axel群体之间的这种合作伙伴关系，具有转基因和嗅觉生物学方面的专业知识，以及具有测序，基因组进化和cDNA阵列技术的经验的Trask和Hood群体，代表了团结大型基因组学和功能生物学世界的独特机会。 我们认为，这种功能基因组学上的这种伙伴关系代表了未来协作努力来表征复杂神经生物学系统和大基因家族的模型。