Detecting the motion of odors: Olfactory direction sensing in Drosophila

项目摘要 本计画将探讨嗅觉系统中多感觉整合的神经运算 导航嗅觉导航驱动动物的行为，从那些对人类生存至关重要的行为， 作为作物授粉，到那些具有惊人破坏性的，如人类宿主的位置由载体的 疾病嗅觉导航也是理解神经系统如何将复杂的 将感官刺激转化为包括目标导向任务的动作序列。为了辨别气味，动物 必须整合来自多个感官输入的潜在冲突的信息流，例如机械感官， 来自风运动的信息，以及气味信号的时间和位置。我将重点介绍一个信息 嗅觉中尚未研究的气味流：气味细丝运动的方向。气味的方向 运动可以包含关于气味源的位置的信息，这可以加强来自局部运动的信息。 风的提示。该项目将结合联合收割机复杂的行为范例，遗传沉默，钙成像， 在一个模型系统，果蝇黑腹果蝇，理论建模，以表征气味运动 被探测到并用于自然羽流导航。有针对性的神经操纵是由丰富的 果蝇系统中可用的遗传工具-特别是最近识别的神经元类型（和 高级嗅觉处理中心的遗传驱动的发展。在辅导（K99）部分， 在这项资助下，我将使用行为记录和光遗传学刺激来表征气味方向感， 果蝇，以及它如何与风的感应相结合。在K99的后半部分， 在R 00阶段，我将使用靶向遗传操作和钙成像来识别神经元和大脑 参与气味方向感知的区域，并表征气味方向如何在活动中编码 二阶和三阶嗅觉回路神经元的模式。该项目的这一部分是唯一可能在 果蝇系统，其映射良好的连接体允许信息流的因果扰动， 嗅觉回路的层次结构在R 00的后半部分，我将结合联合收割机理论模型和行为 记录来量化气味方向感测的信息如何在导航中得到最佳利用 自然的气味该提案提供了记录神经活动的培训，以及 导航分析和高阶嗅觉处理的设计。培训将由一个强大的 导师和咨询委员会，由共同导师蒂埃里埃莫内和达蒙克拉克，谁提供 在果蝇嗅觉导航和方向感在果蝇视觉互补的专业知识 途径，以及顾问Justus Verdegli（嗅觉导航的虚拟现实分析），James Jeanne （果蝇高级嗅觉中心的计算）和Jing Yan（专业发展）。这些 培训视野将有助于成功过渡到科学独立，导致我的长期 目标是表征行为学相关的、目标导向的任务背后的神经回路和计算。

Project Summary This project will investigate the neural computations underlying multisensory integration in the context of olfactory navigation. Olfactory navigation drives animal behaviors ranging from those critical for mankind’s survival, such as crop pollination, to those that are fantastically destructive, such as the location of human hosts by vectors of disease. Olfactory navigation is also an ideal paradigm for understanding how neural systems convert complex sensory stimuli into sequences of actions comprising a goal-directed task. To navigate odor plumes, animals must integrate potentially conflicting information streams from multiple sensory inputs, such as mechanosensory information from wind motion, as well as the timing and location of odor signals. I will focus on an information stream not yet investigated in olfaction: the direction of motion of traveling odor filaments. The direction of odor motion may contain information about the location of the odor source, which can reinforce information from local wind cues. This project will combine sophisticated behavioral paradigms, genetic silencing, calcium imaging, and theoretical modeling in a model system, the fruit fly Drosophila melanogaster, to characterize how odor motion is detected and used in natural plume navigation. Targeted neural manipulations are enabled by the wealth of genetic tools available in Drosophila system – in particular the recent identification of neuron types in (and development of genetic drivers for) higher-order olfactory processing centers. In the mentored (K99) portion of this grant, I will use behavioral recordings and optogenetic stimulation to characterize odor direction sensing in fruit flies, and how it integrates with wind sensing. In the latter portion of the K99, carrying over into the initial phase of the R00, I will use targeted genetic manipulations and calcium imaging to identify the neurons and brain regions involved in odor direction sensing, and to characterize how odor direction is encoded in the activity patterns of 2nd- and 3rd-order olfactory circuit neurons. This portion of the project is uniquely possible in the Drosophila system, whose well-mapped connectome allows causal perturbations of the information flow through the olfactory circuit hierarchy. In the latter portion of the R00, I will combine theoretical models with behavioral recordings to quantify how information from odor direction sensing can be optimally exploited in navigating naturalistic odor plumes. The proposal offers training in recording neural activity, as well as mentorship in the design of navigation assays and higher-order olfactory processing. Training will be provided by a strong mentorship and advising committee, consisting of co-mentors Thierry Emonet and Damon Clark, who offer complementary expertise in Drosophila olfactory navigation and in direction sensing in the Drosophila visual pathway, as well as advisors Justus Verhagen (virtual reality assay for olfactory navigation), James Jeanne (computations in Drosophila higher-order olfactory centers), and Jing Yan (professional development). These training horizons will facilitate a successful transition to scientific independence, leading toward my long-term goal of characterizing the neural circuits and computations underlying ethologically-relevant, goal-directed tasks.