Pannexin channels in tissue inflammation and metabolite release

项目1项目总结 组织环境中的细胞之间的通信对于许多生理上的 流程。在组织内吞噬细胞如何去除凋亡细胞的背景下，我们最初 观察到通过PAnnexin-1(Panx1)通道从凋亡细胞释放的核苷酸，如ATP和UTP 并作为“找到我的信号”来吸引吞噬细胞，导致身体迅速被移走。后续工作 (与其他三个项目负责人合作)确定了C端依赖于caspase的切割 作为Panx1通道开放的机制之一。在过去的几年里，我们直接通过项目1， 已经提出了几点关键意见，这些意见构成了目前这一更新的基础。其中包括身份识别 一种新的Panx1通道抑制剂曲瓦沙星的合成及其在细胞凋亡中的新作用(Poon ET 等人，《自然》杂志，2014)；确定螺内酯是一种新的Panx1抑制剂，并证明了其重要性 螺内酯介导Panx1抑制调节血压(Good等人，Circ Research 2017)；鉴定了一种新的Panx1激活剂；产生了一种新的转基因小鼠，能够诱导 过表达Panx1；以及通过双杂交筛选鉴定Panx1(激酶Sik)的新结合伙伴。 项目1还生成了一些新的鼠标工具，被PPG的其他成员广泛使用。 在这个项目1中，我们旨在测试Panx1通过以下途径控制炎症过程的中心假设 以及非嘌呤能信号，从根本上改变了Panx1的当前视角。在目标1中， 我们将测试一个新的概念(来自我们的初步研究)，即Panx1通道可以释放嘌呤能和 直接影响细胞间通讯的非嘌呤能代谢物，以及抗炎基调 在局部组织环境中。我们还将测试一种新发现的Panx1激动剂甲氧曲明的作用，以及 这是否也会影响通过Panx1释放新的代谢物。在目标2中，基于我们初步的 研究表明Panx1通道是限制呼吸道炎症所必需的，我们将测试Panx1在呼吸道中的作用 使用我们最近建立的模型来治疗疾病(han等人，《自然》2016)。此外，基于新的Panx1 我们确定的互动伙伴Sik，我们将探索呼吸道中Panx1要求的机械方面 发炎。总而言之，我们期待这些研究为pannin通道如何发挥作用提供新的见解。 在体内的不同环境下，识别刺激Panx1功能的新模式，并更好地定义Panx1- 依赖于细胞间通讯来调节组织中的炎性基调。新的鼠标线， 由项目1确定的小分子调节器和蛋白质相互作用元件将与另一个无缝集成 本P01中有三个项目和核心。

PROJECT 1 PROJECT SUMMARY Communication between cells within a tissue environment is fundamentally important for many physiological processes. Working in the context of how apoptotic cells are removed by phagocytes within tissues, we initially observed that nucleotides such as ATP and UTP released from apoptotic cells via Pannexin-1 (Panx1) channels and act as ‘find-me signals’ to attract phagocytes, leading to the prompt removal of corpses. Subsequent work (in collaboration with the other three Project leaders) identified a caspase-dependent cleavage of the C-terminus of Panx1 as one of the mechanisms of Panx1 channel opening. In the past few years, directly via Project 1, we have made several key observations that form the basis of this current renewal. These include the identification of a new Panx1 channel inhibitor trovafloxacin and demonstrating a novel role for Panx1 in apoptosis (Poon et al., Nature 2014); identifying spironolactone as a new inhibitor of Panx1 and demonstrating the importance spironolactone mediated Panx1 inhibition in regulating blood pressure spironolactone (Good et al., Circ Research 2017); identified a new activator of Panx1; generating a new transgenic mouse capable of inducibly overexpressing Panx1; and, identification of new binding partners of Panx1 (kinase SIK) via a two-hybrid screen. Project 1 has also generated a number of new mouse tools that are widely used by other members of the PPG. In this Project 1, we aim to test the central hypothesis that Panx1 controls inflammatory processes through purinergic as well as non-purinergic signals, fundamentally shifting the current perspective on Panx1. In Aim 1, we will test a new concept (from our preliminary studies) that Panx1 channels can release both purinergic and non-purinergic metabolites that influence inter-cellular communication directly, and the anti-inflammatory tone within the local tissue milieu. We will also test the role of a newly identified Panx1 agonist methoctramine, and whether this can also influence the release of novel metabolites via Panx1. In Aim 2, based on our preliminary studies that Panx1 channels are required for limiting airway inflammation, we will test the role of Panx1 in airway disease using models we have recently established (Han et al., Nature 2016). Further, based on the new Panx1 interacting partner SIK that we identified, we will probe the mechanistic aspects of Panx1 requirement in airway inflammation. Collectively, we expect these studies to provide new insights on how pannexin channels function in different contexts in vivo, identify new modes of stimulating Panx1 function, and better define Panx1- dependent intercellular communication toward regulating the inflammatory tone in tissues. The new mouse lines, small molecule modulators, and protein interactors identified by Project 1 will integrate seamlessly with the other three projects and cores within this P01.