Role of Pannexin-1 in sensory systems

Pannexin1 （Panx1）是pannexin基因家族的三个完整膜蛋白之一，其特征是不同的翻译后蛋白修饰、亚细胞定位和广泛的组织分布，包括大脑和感觉器官。目前的知识是Panx1形成电压门控通道。这些通道似乎参与了嘌呤能、肾上腺素能、瞬时受体电位香草蛋白和NMDA受体下游的细胞信号级联反应。进一步的证据表明，Panx1通道通过细胞外K+和Zn2+升高、细胞内Ca2+增加、机械刺激、电压、caspase介导的裂解、氧化还原调节、激酶、NMDA刺激或细胞外ph的变化进行复杂的调节。总之，Panx1通道在整个脊椎动物体内具有复杂的调节和多种生理作用。******这项研究计划的长期目标是了解Panx1在大脑和感觉系统突触传递中的生理作用，重点是视觉系统。当前研究计划的更新有三个目标，测试Panx1生物学的不同但互补的方面。他们将在体外使用基于细胞的方法进行测试，在体内使用TALEN技术产生的转基因斑马鱼进行测试。目的1探讨Panx1从er -高尔基复合体转运到细胞膜时，磷酸化作为“停-走”信号的调节作用。目的2探究当Panx1到达细胞表面时，细胞外pH值如何调节Panx1通道。目的3将研究斑马鱼Panx1基因的基因消融如何影响影响感觉和运动行为的主要信号通路。在接下来的五年里，主要成果将填补围绕Panx1渠道功能的重大知识空白。******总之，我提出了一种高度协同和创新的方法，使用体外和体内的方法。预期的结果将为Panx1通道调节和聚集在这个分子中心的信号通路的整合提供新的机制见解。受训者将参与各个层次的研究，并在这个充满活力和挑战性的项目中获得广泛的技能。最后，提案中使用的独特斑马鱼模型将提供给其他希望利用我们的动物模型来研究其他基本生物学问题，或毒理学，药物筛选或生物医学/生物工程研究的人。**

Pannexin1 (Panx1) is one of three integral membrane proteins of the pannexin gene family characterized by distinct post-translational protein modifications, subcellular localization, and broad tissue distribution including the brain and sensory organs. Current knowledge is that Panx1 forms voltage gated channels. These channels appear involved in the cell-signaling cascades downstream of the purinergic, adrenergic, transient receptor potential vanilloid, and NMDA receptors. Further evidence suggests a complex regulation of Panx1 channels by elevated extracellular K+ and Zn2+, increased intracellular Ca2+, mechanical stimulation, voltage, caspase-mediated cleavage, redox regulation, kinases, NMDA stimulation, or changes in extracellular pH. Together, Panx1 channels represent a significant molecular hub with complex regulation and multiple physiological roles throughout the vertebrate body. ******The long-term objective of this research program is to understand the physiological role of Panx1 in synaptic transmission in the brain and sensory systems, with a focus on the visual system. The renewal of the current research program has three objectives testing distinct, but complementary aspects of Panx1 biology. They will be tested in vitro using cell-based approaches and in vivo using transgenic zebrafish generated by TALEN technology. Objective#1 inquires the regulatory role of phosphorylation as a “stop-go” signal when Panx1 is transported from the ER-Golgi complex to the cell membrane. Objective #2 inquires how extracellular pH regulates Panx1 channels when Panx1 has arrived at the cell surface. Objective #3 will investigate how genetic ablation of Panx1 genes in the zebrafish affects major signaling pathways, which impact sensory and motor behaviors. In the next five years, primary outcomes are poised to close significant knowledge gaps surrounding Panx1 channel function. ******In summary, I propose a highly synergistic and innovative approach using in vitro and in vivo methodology. The expected outcomes will provide novel mechanistic insight into Panx1 channel regulation and integration of signaling pathways converging on this molecular hub. Trainees will engage in this research at all levels and in the process acquire a broad skill set in a vibrant and challenging program. Finally, the unique zebrafish models used in the proposal will be made available for others who wish to pursue studies exploiting our animal models for investigating other fundamental biological questions, or for toxicology, drug screening, or biomedical/bioengineering research. **