Junctional multiprotein signaling complexes in sensory neurons

为了感知和评价环境，哺乳动物被配备了外周神经(外周体感系统)。这些神经贯穿我们的身体，收集关于周围环境的僵硬、温度和化学成分的信息，也收集关于我们自身身体完整性的信息。这些神经配备了各种分子传感器，对特定的外部刺激做出反应，将这些传感器转化为统一的电脉冲(动作电位)，然后发送到大脑进行解释。单一的体感神经经常表达各种不同的传感器或感觉机制，这些传感器或感觉机制对不同的刺激做出反应，但一条神经产生的输出信号非常相似。该领域的一个主要难题是单个感觉神经细胞如何具体解释不同类型的信号；这项提议的主要目的是阐明这个问题。基于大量的初步数据和我们等人发表的工作，我们假设这种细胞内信号特异性的一种机制在于将不同的细胞内信号机制组装成不同的、物理上相关的蛋白质复合体。这样一种信令机制与另一种信令机制的物理分离使它们能够使用共同的信令事件和信使分子，而不会混淆消息的含义。我们将专注于一种这样的多蛋白复合体，它负责身体对组织炎症(即炎性疼痛)的检测。我们已经证实，在一些感觉神经中存在复杂的多蛋白信号复合体，它们将炎症化学介质的受体和一些信号蛋白聚集在一起，这些受体是这些受体的靶标。然而，关于这些复合体的整体组成、其组成部分的功能排列、与其他信号机制的关系、这些复合体是动态的还是静态的，或者这些复合体是否可以被操纵以达到治疗效果，人们几乎一无所知。我们的项目旨在回答这些耐人寻味的问题。我们有三个具体的目标：1)揭示感觉神经中炎性多蛋白信号复合体的分子组成；2)阐明这些复合体的功能意义；3)为科学和治疗目的开发具有复杂完整性的操作策略。我们开发了一种全面的、多学科的方法，其中神经元通信机制的保真度、特异性和局部化将在其复杂性中得到阐明。这种方法结合了诺贝尔奖获得者超分辨率显微镜、蛋白质组学、分子和结构生物学方法以及活体研究等尖端方法。我们相信，这项研究将把我们对哺乳动物感觉系统，特别是炎性疼痛机制的理解带到一个新的洞察力水平。重要的是，我们的发现可能会形成止痛药开发和疼痛管理的新方法。

In order to perceive and evaluate the environment mammals are equipped with peripheral nerves (peripheral somatosensory system). These nerves run through our body and collect information about rigidity, warmth and chemical composition of the surrounding milieu and also about our own body's integrity. These nerves are equipped with various molecular sensors that respond to specific external stimuli, transforming these into the uniform electrical impulses ('action potentials') that are then sent to the brain for interpretation. Single somatosensory nerve often expresses a variety of different sensors or sensory mechanisms that respond to distinct stimuli, yet the output signals produced by a nerve are very similar. A major conundrum in the field is how different types of signals are specifically interpreted by a single sensory nerve cells; the main aim of this proposal is to shed light on this question. Based on the wealth of preliminary data and published work from our group and others we hypothesize that one mechanism for such intracellular signal specificity lies in the assembly of different intracellular signaling mechanisms into distinct, physically associated protein complexes. Such physical separation of one signaling machinery from another allows them to use common signaling events and messenger molecules without 'mixing up' the meaning of the message. We will focus on one such multiprotein complex which is responsible for body's detection of tissue inflammation (i.e. inflammatory pain). We have already established that there are intricate multiprotein signaling complexes in some sensory nerves that bring together receptors for chemical mediators of inflammation and some signaling proteins that are targeted by these receptors. However, hardly anything is known about the overall constitution of these complexes, functional arrangements of their components, relationships with other signalling mechanisms, whether these complexes are dynamic or static or whether these can be manipulated for therapeutic benefits. Our project aims to answer these intriguing questions. We have three specific aims: 1) to reveal molecular composition of the inflammatory multiprotein signaling complexes in sensory nerves; 2) to elucidate functional significance of these complexes; 3) to develop strategies for manipulations with complex integrity for scientific and therapeutic purposes. We developed a comprehensive and multidisciplinary approach in which fidelity, specificity and localization of neuronal communication mechanisms will be elucidated in their complexity. This approach combines cutting-edge methods such as Nobel Prize winning super-resolution microscopy, proteomics, molecular and structural biology approaches and in vivo studies. We are confident that this research will bring our understanding of mammalian sensory systems and, particularly, of inflammatory pain mechanisms, to a new level of insight. Importantly, our findings may shape new approaches for analgesic drug development and pain management.