Development and Optimization of a Digital AC-DC Electropenetrograph for Real-Time Recording of On-host Tick Feeding

堪萨斯州立大学(与美国农业部农业研究服务和哈维·穆德学院合作)被授予设计、制造和测试数字交-直流电穿透仪，以TICKS作为模型系统，研究食血节肢动物的实时摄食行为。扁虱和其他食血节肢动物传播了广泛的医学和兽医重要病原体，其中许多因气候变化而日益加剧。扁虱取食行为基础研究的一个重要障碍是无法捕捉观察和统计分析取食行为的细节，因为它隐藏在宿主皮肤表面之下。令人难以置信的长时间的取食使这一挑战进一步复杂化(成虫的取食时间约为7至10天)。为了解决这一方法缺陷，该项目将开发一种用户和应用友好的数字交-直流电穿透仪，使研究人员能够轻松地以前所未有的细节调查这些隐藏的行为。该项目汇集了一个跨学科的科学家团队，他们将共同支持12至20名本科生和一名博士后研究人员的培训，使他们有机会从工程、计算机科学和生物学的不同角度探索这一新兴的研究兴趣领域。项目本科生和博士后研究员将在项目科学家指导和指导的团队中工作。学员被尽可能广泛地招募，他们将与来自学术界、政府和行业的科学家互动，为他们提供调查未来职业道路的机会。受训者将参与这项研究的智力和身体方面的工作，并将参与对他们的设计进行迭代评估，这些设计使用节肢动物的组合进行测试：扁虱(项目模型食血节肢动物)和蚜虫(电穿透术研究的黄金标准昆虫)。项目科学家和受训人员还将有机会通过社区和科学交流平台和活动(如堪萨斯科学博览会)，通过开发和提供相关内容和体验机会，与更广泛的受众分享项目目标。电子穿透术(EPG)是一种已使用了近65年的变革性技术，用于研究刺吸式、植食性昆虫的蒙面取食行为。然而，这种实时研究食血节肢动物基本行为的方法，包括摄食时间极长(几天到几周)的扁虱，几十年来一直没有得到生物学家的支持。尽管使用现有的模拟交直流电穿透仪对扁虱和蚊子的摄食记录取得了初步成功，但该仪器在处理脊椎动物宿主上的食血节肢动物方面存在显著的物理限制。开发一种用户和应用更友好的数字交-直流电穿透仪将解决这一挑战，并使开创性的调查能够检测、表征和量化扁虱和其他食血节肢动物进行的渐进和高度协调的摄食行为。然后，可以进行假设驱动的研究，以研究基本的摄食生物学，并调查宿主因素、媒介特征、病原体和化学干预如何具体地改变隐藏的节肢动物的觅血行为。在本项目中，将通过三个科学目标对数字交-直流电穿透仪进行评估：(I)设计和制造一个数字交-直流电穿透仪原型，以记录在未注射镇静剂的活体宿主上摄食扁虱的情况；(Ii)反复评估原型仪器的活体和活体宿主版本，并根据需要修改原型；以及(Iii)展示数字交-直流电穿透仪在记录和统计比较应用行为抑制化合物时的摄食行为的可用性。这项研究的成功完成将带来一种用户友好的、可商业化的仪器和相关软件，它将：1)加快电穿透技术从植物食性昆虫到食血节肢动物的扩展；2)通过不断发展的数字仪器设计，确保这一关键基础设施的持续可用；3)通过与开发相关的机器学习软件，实现更快的高通量使用。项目成果将包括开发一种用户友好的数字交-直流电穿透仪，并支持“节肢动物种类灵活”软件。这一新颖的研究工具将为广大研究人员带来新的机会，他们有兴趣通过吸血和植物喂养节肢动物来提高动植物农业的弹性。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

An award is made to Kansas State University (in collaboration with USDA Agricultural Research Service and Harvey Mudd College) to design, build, and test a digital AC-DC electropenetrograph to study the real-time feeding behaviors of blood-feeding arthropods, using ticks as the model system. Ticks and other blood-feeding arthropods transmit a wide array of medically- and veterinary-important pathogens, many of these increasingly exacerbated by climate change. An important obstacle to basic research on tick feeding behavior is the inability to capture observations and statistically analyze details of tick feeding behavior because it is masked below the surface of the host’s skin. The challenge is further compounded by the incredibly long durations over which ticks feed (~7 to 10 days for adult ticks). To address this methodological deficit, this project will develop a user- and application-friendly digital AC-DC electropenetrograph which will enable researchers to readily investigate these hidden behaviors in unprecedented detail. This project brings together a transdisciplinary team of scientists that will collectively support the training of 12 to 20 undergraduates and a postdoctoral researcher, giving them opportunities to explore this burgeoning area of research interest from diverse perspectives of engineering, computer science, and biology. Project undergraduates and the postdoctoral researcher will work in teams mentored and guided by project scientists. Trainees, recruited as broadly as possible, will interact with scientists from academia, government, and industry, affording them opportunities to investigate future career paths. Trainees will be involved in both intellectual and physical aspects of this research and will participate in the iterative evaluation of their designs tested using a combination of arthropod species: ticks (project model blood-feeding arthropod) and aphids (gold standard insect for electropenetrography research). Project scientists and trainees will also have opportunity to share project goals with broader audiences through development and delivery of related content and experiential opportunities through community and science communication engagement platforms and events (e.g. Kansas Science Fair).Electropenetrography (EPG) is a transformational technology that has been used for nearly 65 years to study the masked feeding behaviors of piercing-sucking, plant-feeding insects. However, such a means of studying the basic behaviors of blood-feeding arthropods in real time, including ticks that feed for extreme durations (days to weeks), has eluded biologists for decades. Despite initial success with tick and mosquito feeding recordings using the existing analog AC-DC electropenetrograph, this instrumentation presents notable physical limitations for working with blood-feeding arthropods on vertebrate hosts. Developing a more user- and application-friendly digital AC-DC electropenetrograph will solve this challenge and enable ground-breaking investigations to detect, characterize, and quantify the progressive and highly coordinated feeding behaviors performed by ticks and other blood-feeding arthropods. Hypothesis-driven studies can then be performed to study basic feeding biology and investigate how host factors, vector characteristics, pathogens, and chemical interventions specifically modify hidden arthropod blood-feeding behaviors. In this project, the digital AC-DC electropenetrograph will be evaluated over the course of three scientific objectives: (i) Design and build a prototype digital AC-DC electropenetrograph and associated software to record tick feeding on an unsedated live host; (ii) Iteratively evaluate versions of the prototype instrument with live ticks and live host, and modify prototype as needed; and, (iii) Demonstrate the usability of the digital AC-DC electropenetrograph to record and statistically compare tick feeding behaviors upon applications of a behavior-interdicting compound. Successful completion of this research will deliver a user-friendly, commercializable instrument and associated software that will: 1) accelerate expansion of electropenetrography from plant-feeding insects into blood-feeding arthropods, 2) ensure the continued availability of this crucial infrastructure through an evolved digital instrument design, and 3) allow faster high-throughput uses through development-associated machine learning software. Project outcomes will include development of a user-friendly, digital AC-DC electropenetrograph and supporting ‘arthropod species flexible’ software. This novel research instrument will spur new opportunity for a broad community of researchers interested in improving the resiliency of animal and plant agriculture from blood-feeding and plant feeding arthropods.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.