Pannexin channels in tissue inflammation and metabolite release

项目1项目概要 组织环境内的细胞之间的通信对于许多生理学过程来说是根本重要的。 流程.在组织内吞噬细胞如何清除凋亡细胞的背景下，我们最初 观察到核苷酸如ATP和UTP通过Pannexin-1（Panx 1）通道从凋亡细胞释放 并作为“找到我的信号”来吸引吞噬细胞，从而迅速清除尸体。后续工作 (in与其他三个项目负责人合作）确定了C-末端的半胱天冬酶依赖性切割 作为Panx 1通道开放的机制之一。在过去的几年里，直接通过项目1，我们 提出了几项重要意见，这些意见构成了本次更新的基础。其中包括识别 一种新的Panx 1通道抑制剂trovaflavine，并证明了Panx 1在细胞凋亡中的新作用（Poon et 例如，Nature 2014）;将螺内酯鉴定为Panx 1的新抑制剂，并证明其重要性 在调节血压中螺内酯介导的Panx 1抑制螺内酯（Good等，Circ研究 2017年）;确定了一种新的Panx 1激活剂;产生了一种新的转基因小鼠，能够诱导 过表达Panx 1;以及，通过双杂交筛选鉴定Panx 1的新结合伴侣（激酶SIK）。 项目1还产生了许多新的鼠标工具，被PPG的其他成员广泛使用。 在这个项目1中，我们的目标是测试中心假设，即Panx 1通过以下途径控制炎症过程： 嘌呤能和非嘌呤能信号，从根本上改变了目前对Panx 1的看法。在目标1中， 我们将测试一个新的概念（从我们的初步研究），Panx 1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， 在局部组织环境中。我们还将测试一种新发现的Panx 1激动剂methoctramine的作用， 这是否也可以通过Panx 1影响新代谢物的释放。在目标2中，根据我们初步的 为了研究Panx 1通道对限制气道炎症的作用，我们将检测Panx 1在气道炎症中的作用。 疾病使用我们最近建立的模型（Han等人，Nature 2016）。此外，基于新的Panx 1 我们确定的相互作用伙伴SIK，我们将探讨气道Panx 1需求的机制方面， 炎症总的来说，我们希望这些研究能够为泛连接蛋白通道的功能提供新的见解 在不同的情况下，在体内，确定刺激Panx 1功能的新模式，并更好地定义Panx 1- 依赖于细胞间通讯调节组织中的炎症张力。新的鼠标线， 小分子调节剂和项目1确定的蛋白质相互作用剂将与其他药物无缝整合。 P01中的三个项目和核心。

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.