BIOLOGY OF SPATIOTEMPORAL NITRIC OXIDE GRADIENTS

在这个建议中要研究的中心原则是，一氧化氮（NO）是一种细胞信号分子，细胞毒性的介体不仅取决于它在给定点的瞬时浓度，而且还取决于它的浓度梯度。目前用于NO研究的方案不允许NO的生物相关浓度梯度的空间释放，也不允许以精细分辨率直接时间和空间检测NO。该提案的一个重要目标是开发提供NO时空检测的新型荧光探针和供体，并开发用于明确定义的NO时空释放的新方法。为了更好地理解NO梯度在介导细胞信号传导和细胞毒性中的作用，在COBRE IDEA提案中进行的研究将垂直整合五个医学相关的研究项目，这些项目采用独特的，但补充实验系统。这些新型NO试剂将在整个提案中使用，并将专门用于本项目，以检验一氧化氮是精子趋化分子的假设。由于NO与老年人的肠功能障碍有关，项目2将采用老年大鼠模型系统来研究肠神经系统内神经和胃肠道NO信号的改变是否涉及肠神经系统内神经和胃肠道NO信号的改变。项目3将阐明特定的细胞生理学，病理学和信号通路，涉及上呼吸道上皮细胞中NO的产生及其在加重和/或减轻呼吸道病原体引起的疾病中的作用。项目4将使用小鼠逆转录病毒模型研究NO在逆转录病毒诱导的神经变性中的作用。这项研究将提供深入了解NO在HV诱导的神经系统疾病中的潜在作用。最后，项目5将研究NO在控制专性细胞内细菌人类病原体感染中的作用。还将研究细菌对NO应激的反应。这些研究不仅将导致开发具有广泛适用性的新型NO释放和检测试剂，它们还将提供对NO作为信号分子的作用以及作为人类疾病进展中的保护性或破坏性因素的更好理解。

The central tenet to be investigated in this proposal is that nitric oxide (NO) is a cell signaling molecule and mediator of cytotoxicity is not just dependent upon its instantaneous concentration at a given point, but rather it is also dependent upon its concentration gradient. The protocols that are currently in use for NO research do not allow the spatial release of biologically relevant concentration gradients of NO, nor do they allow the direct temporal and spatial detection of NO with fine resolution. An important goal of this proposal is to develop novel fluorescent probes and donors that afford spatiotemporal detection of NO, and to develop new methods for well defined spatiotemporal release of NO. To achieve a greater understanding of the role of NO gradients in mediating cell signaling and cytotoxicity, the research conducted in this COBRE IDeA proposal will vertically integrate five medically relevant research projects that employ unique but complementary experimental systems. These novel NO reagents will be used throughout this proposal and will be specifically used in this project to test the hypothesis that nitric oxide is a sperm chemotactic molecule. Because NO has been implicated in bowel dysfunction in the elderly, Project 2 will employ an aged rat model system to investigate whether alterations in neural and gastrointestinal NO signaling within the enteric nervous system of the bowel investigate whether alterations in neural and gastrointestinal NO signaling within the enteric nervous system of the bowel are involved. Project 3 will elucidate specific cell physiology, pathology, and signaling pathways involving NO production in the upper airway epithelium and its role in exacerbating and/or moderating disease caused by respiratory tract pathogens. Project 4 will investigate the role of NO in retrovirus-induced neurodegeneration using a murine retrovirus model. This investigation will provide insight into the potential role of NO in HV-induced neurological disease. Finally, Project 5 will examine the role of NO in controlling infection by obligate intracellular bacterial human pathogens. The bacterial response to NO stress will also be investigated. Not only will these studies lead to the development of novel NO release and detection reagents with broad scale applicability, they will also provide a greater understanding of the role of NO as a signaling molecule, and as protective or damaging factor in the progression of human disease.