Diversity and Convergence in Fish Olfactory Subsystems

鱼类嗅觉子系统的多样性和趋同性

• 批准号: RGPIN-2019-06402
• 负责人: Zielinski, Barbara
• 金额: $ 2.91万
• 依托单位: University of Windsor
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=738891
• 关键词: Diversity; Convergence; Fish; Olfactory; Subsystems

Fish utilize olfaction for feeding, alarm response, spawning migration, mate attraction and kin recognition. The neurons that respond to specific odorants project into separate glomerular clusters in the olfactory bulb of the brain. These glomeruli are the functional units of odorant discrimination, and the study of glomerular patterning is a valuable tool to assess the responsiveness to specific odorants. Knowledge of glomerular connections to specific higher brain structures is an indicator of the animal's response to an odorant. Recent studies have revealed much about glomerular mapping and functionality in zebrafish, however considerably less is known regarding the functional organization of the olfactory system in non-model fish. The goal of this research program is to map out glomerular function of the olfactory system in three fish: the sea lamprey, salmon and round goby. Olfaction has a dominant role in guiding behaviour in sea lamprey, a basal vertebrate. Both salmon and gobies are teleost fish. Salmon utilize olfactory signals during spawning migration and gobies use olfactory cues to attract mates. There are distinct main and accessory olfactory subsystems in lampreys, but a single olfactory system with different types of olfactory sensory neurons intermingling in the olfactory epithelium of teleost fish. There are three objectives.  Objective 1 focuses on medial glomeruli. In lampreys, these contain input from the accessory olfactory organ and neural output to a neural relay that controls movement. Objective 1a is to investigate chemoreceptive properties of individual cells in the lamprey accessory olfactory organ. The findings will determine if these neurons are generalists that stimulate movement in response to many odorants. Objective 1b is to probe for the bulbar glomeruli of olfactory sensory neuron crypt cells in salmon and goby, as these may project to medial glomeruli that input olfactory information during reproduction and kin recognition. Objective 2 is to compare odorant responses and neural projections for four non-medial glomeruli. For example, lateral glomeruli appear to be dedicated to amino acid chemoreception, from lampreys to salmon. Objective 3 is to produce a synthesis of bulbar organization in fish by mapping the glomeruli in these three fish. These maps will include olfactory sensory neuron input, glomerular organization, odorant mapping and output projections. This knowledge is important for understanding the neurobiology behind the organization of the olfactory system in species that survive under natural selection pressure. Knowledge of olfactory function is also valuable to the management of fish populations for conservation and habitat restoration. For example, the neurobiology of olfaction is particularly well described in insects and resulting concepts have driven novel approaches to pest control.

鱼类利用嗅觉来觅食、警报反应、产卵迁徙、吸引配偶和识别亲属。对特定气味作出反应的神经元投射到大脑嗅球中单独的肾小球簇中。这些肾小球是气味辨别的功能单位，肾小球模式的研究是评估对特定气味的反应性的有价值的工具。了解肾小球与特定高级脑结构的联系是动物对气味反应的一个指标。最近的研究已经揭示了斑马鱼肾小球的定位和功能，但对非模式鱼嗅觉系统的功能组织知之甚少。这项研究计划的目标是绘制出三种鱼类嗅觉系统的肾小球功能：海七鳃鳗、鲑鱼和圆虾虎鱼。嗅觉在指导海七鳃鳗（一种基底脊椎动物）的行为中起着主导作用。鲑鱼和虾虎鱼都是硬骨鱼。鲑鱼在产卵迁徙时利用嗅觉信号，虾虎鱼利用嗅觉信号吸引配偶。在硬骨鱼的嗅觉上皮中，七鳃鳗有不同的主嗅觉子系统和副嗅觉子系统，但有一个由不同类型的嗅觉感觉神经元组成的单一嗅觉系统。有三个目标。目的1关注内侧肾小球。在七鳃鳗中，这些包括来自副嗅觉器官的输入和神经输出到控制运动的神经继电器。目的1a是研究七鳃鳗副嗅觉器官中单个细胞的化学感受特性。研究结果将确定这些神经元是否是多面手，对许多气味做出反应时刺激运动。目的1b是探索鲑鱼和虾虎鱼嗅感觉神经元隐窝细胞的球状肾小球，因为这些细胞可能投射到内侧肾小球，在繁殖和亲属识别过程中输入嗅觉信息。目的2是比较四个非内侧肾小球的气味反应和神经投射。例如，从七鳃鳗到鲑鱼，侧肾小球似乎专门用于氨基酸化学接受。目的3是通过绘制这三种鱼的肾小球来合成鱼的球组织。这些图将包括嗅觉感觉神经元输入、肾小球组织、气味映射和输出投影。这些知识对于理解在自然选择压力下生存的物种嗅觉系统组织背后的神经生物学是很重要的。嗅觉功能的知识对鱼类种群的保护和栖息地恢复的管理也很有价值。例如，嗅觉的神经生物学在昆虫中得到了很好的描述，由此产生的概念推动了害虫控制的新方法。