Detecting the motion of odors: Olfactory direction sensing in Drosophila

项目摘要 这个项目将在嗅觉的背景下研究潜在的多感觉整合的神经计算 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，比如 作为作物授粉，对于那些极具破坏性的物种，例如通过媒介确定人类寄主的位置 疾病。嗅觉导航也是了解神经系统如何将复杂的 将感官刺激转化为一系列动作，构成目标导向的任务。导航气味羽流、动物 必须集成来自多个感觉输入(例如机械感觉)的潜在冲突信息流 来自风向的信息，以及气味信号的时间和位置。我会集中在一个信息上 尚未研究嗅觉的气流：移动气味细丝的运动方向。气味的方向 运动可能包含有关气味来源位置的信息，这可以加强来自本地的信息 风的信号。该项目将结合复杂的行为范例、遗传沉默、钙成像和 果蝇黑腹果蝇模型系统中的理论建模，以表征气味如何运动 被检测到并用于自然羽流导航。有针对性的神经操作是由丰富的 果蝇系统中可用的遗传工具--特别是最近在(和) 开发)高级嗅觉处理中心的遗传驱动因素。在的指导(K99)部分 在这项资助中，我将使用行为记录和光遗传刺激来表征气味方向感知 果蝇，以及它如何与风传感相结合。在K99的后半段，延续到最初的 在R00阶段，我将使用有针对性的基因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，并表征气味方向是如何在活动中编码的 二级和三级嗅觉回路神经元的模式。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通过 嗅觉电路的层次结构。在R00的后半部分，我将把理论模型与行为模型结合起来 量化气味方向感测信息如何在导航中得到最佳利用的记录 自然主义的气味羽流。该提案提供了记录神经活动的培训，以及 导航测试和高阶嗅觉处理的设计。培训将由实力雄厚的 导师和咨询委员会，由共同导师Thierry Emonet和Damon Clark组成，他们提供 果蝇嗅觉导航和果蝇视觉方向感知的互补专业知识 Path，以及顾问Justus Verhgen(用于嗅觉导航的虚拟现实实验)，James Jeanne (在果蝇高级嗅觉中心的计算)，和景燕(专业发展)。这些 训练视野将有助于成功地过渡到科学独立，导致我的长期 描述与行为学相关的、以目标为导向的任务背后的神经回路和计算的目标。

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.