Collaborative Research: Discrimination of Complex Mixtures in Olfactory Signaling

合作研究：嗅觉信号中复杂混合物的辨别

• 批准号: 0641014
• 负责人: Neil Vickers
• 金额: $ 34万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-05-01 至 2011-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0641014&HistoricalAwards=false
• 关键词: Collaborative; Research; Discrimination; Complex; Mixtures

For most of the animals that inhabit our planet the sense of smell is critical for survival. Odors are used to find food, shelter, and mates, as well as to mark territories. Sex pheromones are signals used by many animals, including insects, for the purpose of mate location, and are in almost all cases mixtures of chemicals. The exact blend, ratio and concentration of volatile compounds provides for precise communication between individuals of the same species. Indeed, most smells are mixtures and thus understanding how they are detected and processed by the nervous system is of fundamental interest to research on olfaction in general. Many insects exhibit distinct differences in body form between juvenile and adult stages. The adult antenna (the insect 'nose') is formed during metamorphosis from a patch of tissue known as the antennal imaginal disc. Similar discs give rise to other adult-specific structures such as wings, legs, eyes and genitalia during metamorphosis. The three related moth species that will be used in this project all utilize different mixtures in their sex pheromones. Males of each species have a different set of sensory neurons on the antenna that detect the volatiles present in the unique pheromone mixture released by their females. During metamorphosis the antennal imaginal disc gives rise to all the sensory neurons that will populate the adult antenna. Processes from these neurons called axons grow into the developing brain where they interact with other central neurons to produce the antennal lobe. This structure is comparable to the human olfactory bulb and it is the site where initial processing of olfactory information occurs. Because the antennal imaginal disc is a discrete patch of tissue it can be removed from a caterpillar that is about to enter into the metamorphic stage and transplanted into a host caterpillar of a different species. After metamorphosis, individual male moths that have received a transplanted antenna can be flown in a wind tunnel to determine the odor mixtures that they prefer. Subsequently recordings can be made both from individual hairs that house olfactory sensory neurons on the antenna and central olfactory neurons that populate the antennal lobe. The combination of behavioral and neurophysiological approaches will provide generally applicable insights into the mechanisms that control the wiring of connections between neurons in the brain and how specifically this contributes to the ability of moths and other animals to process and discriminate amongst different odor mixtures. The partnership between investigators at Cornell University and the University of Utah will involve the continued training of a variety of personnel from high school students to undergraduates and visiting scientists who will benefit from exposure to an integrative, collaborative research program. Results from these experiments will be incorporated into classroom teaching and general public outreach activities.

对于居住在我们星球上的大多数动物来说，嗅觉对生存至关重要。气味被用来寻找食物、住所和配偶，以及标记领地。性信息素是包括昆虫在内的许多动物用来寻找配偶的信号，几乎所有情况下都是化学物质的混合物。挥发性化合物的精确混合、比例和浓度为同一物种的个体之间提供了精确的交流。事实上，大多数气味都是混合的，因此了解它们是如何被神经系统检测和处理的，对于一般的嗅觉研究来说是至关重要的。许多昆虫在幼年期和成虫期表现出明显的体形差异。成虫的触角（昆虫的“鼻子”）是由一块被称为触角想象盘的组织在变形过程中形成的。在变态过程中，类似的椎间盘会产生其他成人特有的结构，如翅膀、腿、眼睛和生殖器。在这个项目中使用的三种相关的蛾类都使用不同的性信息素混合物。每个物种的雄性在触角上都有一组不同的感觉神经元，用来检测雌性释放的独特信息素混合物中的挥发物。在变形过程中，天线想象盘产生了所有的感觉神经元，这些神经元将填充成体天线。来自这些被称为轴突的神经元的过程生长到发育中的大脑中，在那里它们与其他中枢神经元相互作用，产生天线叶。这个结构与人类的嗅球相当，它是嗅觉信息初始处理发生的地方。由于触角想象盘是一个离散的组织块，它可以从即将进入变质阶段的毛虫身上取下，移植到不同物种的寄主毛虫身上。在蜕变后，接受了移植天线的雄性飞蛾可以在风洞中飞行，以确定它们喜欢的气味混合物。随后的记录既可以来自位于触角上的嗅觉神经元的单个毛发，也可以来自位于触角叶上的中央嗅觉神经元。行为和神经生理学方法的结合将为控制大脑神经元之间连接的机制提供普遍适用的见解，以及这如何具体有助于飞蛾和其他动物处理和区分不同气味混合物的能力。康奈尔大学（Cornell University）和犹他大学（University of Utah）的研究人员之间的伙伴关系将包括继续培训各种人员，从高中生到本科生，以及访问科学家，他们将受益于一个综合性的合作研究项目。这些实验的结果将被纳入课堂教学和一般的公众推广活动。