Identifying novel tick attractants and repellents by exploiting their olfactory and eco-physiology

项目摘要 在过去的20年里，黑腿蜱，肩胛硬蜱，其分布范围翻了一番。不 令人惊讶的是，根据最近的NIH蜱传疾病，莱姆病的发病率自20世纪90年代以来增加了两倍 战略规划委员会的报告。这些病媒/疾病的扩张归因于气候变化， 社区侵占动物栖息地，以及其他生态变化。多管齐下的战略，特别是 那些基于对蜱独特嗅觉系统和生态生理适应的理解的研究将 提供可纳入现有病媒控制战略的有效做法。蜱虫显示健壮 嗅觉驱动的行为，尽管被赋予了一个简单的嗅觉机制，由ca。20嗅觉感受器 （住房。80-90个嗅觉受体神经元（ORN）。如此简单的嗅觉系统 完成检测和区分首选宿主和配偶的非凡任务，或者， 避免不利的？我们将回答这个问题，通过确定每一个的检测属性， 感受器的气味表现出行为反应的挑战。我们建议使用单个感器 将使用记录（SSR）方法来记录来自各个ORN的气味诱导的活性。 结合气相色谱法（GC-SSR）直接分离生物活性成分的气味， 复杂的气味混合物。这些成分将使用质谱进行化学鉴定，最后 通过将它们注射回GC-SSR进行验证。将对电生理活性化学品进行测试， 行为反应在4臂嗅觉仪-无论是单独或混合。在节肢动物中， 环境中的一系列挥发物在不同的环境中被吝啬地使用，引起不同的行为 例如对宿主和配偶的吸引，以及对不合适的场所的排斥/回避。气味，如 信息素是采样和控制包括蜱虫在内的媒介节肢动物的有效手段，但识别出 有效和有选择性的诱饵至今还难以找到。因此，我们认为， 将导致新的天然引诱剂和驱避剂的发现。该项目将扩展基本的 了解蜱的嗅觉生物学，并将这些知识与生态生理学相结合， 饱和赤字等决定因素将导致设计新的管理策略。

PROJECT SUMMARY Black-legged tick, Ixodes scapularis, have doubled their distribution range within the past 2 decades. Not surprisingly, Lyme disease incidence has tripled since the 1990s according to the recent NIH tickborne diseases strategic planning committee’s report. These vector/disease expansions have been attributed to climate change, neighborhoods encroaching the animal habitats, and other ecologic shifts. Multi-pronged strategies, especially those that are based on understanding the ticks’ unique olfactory system and eco-physiological adaptations will provide effective practices that can be embedded into the existing vector control strategies. Ticks display robust olfactory driven behaviors despite endowed with a simple olfactory machinery made of ca. 20 olfactory sensilla (housing ca. 80-90 olfactory receptor neurons, ORNs). How can such relatively simple olfactory system accomplish the remarkable task of detecting and discriminating between the preferred hosts and mates, or, to avoid the unfavorable ones? We will answer this question by determining the detection properties of each of the sensilla challenging with odors of demonstrated behavioral response. We propose to use the single sensillum recording (SSR) method to record the odor induced activity from individual ORNs, The SSR will be further coupled with gas-chromatography (GC-SSR) to directly isolate biologically active constituents odorant from the complex odors mixtures. These constituents will be chemically identified using mass spectrometry, and finally verified by injecting them back into GC-SSR. Electrophysiologically active chemicals will be tested for the behavioral response in a 4-arm olfactometer- either individually or in blends. In arthropods, a distinct yet limited range of volatiles from the environment are parsimoniously used in various contexts, eliciting distinct behaviors such as attraction to host and mates, and repulsion/avoidance from unsuitable sites. Odors, such as pheromones, are effective means to sample and control vector arthropods including ticks, yet identifying an effective and selective bait has been elusive so far. Therefore we believe that our proposed integrated platform will lead to the discovery of novel natural attractants and repellents. This project will extend the fundamental understanding of the ticks’ olfactory biology, and integrating this knowledge with the eco-physiological determinants such as saturation deficit will lead to design of novel management strategies.