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

项目总结 在过去的20年里，黑腿硬蜱的分布范围扩大了一倍。不 令人惊讶的是，根据美国国立卫生研究院最近的壁虱传播疾病，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/疾病的扩张被归因于气候变化， 侵占动物栖息地的社区，以及其他生态转移。多管齐下的战略，特别是 那些基于对扁虱独特的嗅觉系统和生态生理适应的了解将 提供可嵌入现有病媒控制策略的有效做法。勾号显示健壮 嗅觉驱动的行为，尽管被赋予了一个由大约20个嗅觉感受器组成的简单嗅觉机器 (容纳约80-90个嗅觉感受器神经元，Ons)。这么简单的嗅觉系统怎么可能 完成检测和区分首选寄主和配偶的非凡任务，或 避开不利因素？我们将通过确定每个 用表现出的行为反应的气味挑战感受器。我们建议使用单一感受器 记录(SSR)方法记录单个Orns的气味诱导活动，SSR将进一步 与气相色谱联用(GC-SSR)直接从香料中分离生物活性成分 复杂的气味混合物。这些成分将用质谱仪进行化学鉴定，最后 通过将它们重新注入GC-SSR进行了验证。电生理活性化学物质将被测试 四臂嗅觉仪中的行为反应--单独或混合。在节肢动物中，一种独特但有限的 环境中的一系列挥发物在不同的环境中被节俭地使用，引发了不同的行为 例如对宿主和配偶的吸引，以及对不合适地点的排斥/回避。气味，如 信息素是采样和控制媒介节肢动物(包括扁虱)的有效手段，但识别 到目前为止，有效和选择性的诱饵一直难以捉摸。因此，我们认为我们提出的综合平台 将导致新的天然引诱剂和驱避剂的发现。这个项目将扩展基本的 了解扁虱的嗅觉生物学，并将这一知识与生态生理学相结合 饱和赤字等决定因素将导致新的管理战略的设计。

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.