New Chemical Tools for Exploring Cellular Physiology

摘要 可视化细胞生理学的新化学工具 细胞膜是所有种类的细胞所共有的唯一细胞器。离子分布不均 而穿过质膜的化学物种导致产生电化学 电位，以及这种膜电位或电压的快速变化，驱动了 像神经元和心肌细胞这样的兴奋性细胞。然而，所有细胞，甚至是不可兴奋的细胞，都有一个 膜电位，越来越多的证据支持膜电位在控制 基本细胞生理学--例如，细胞周期、迁移、增殖和分化 不可兴奋的细胞。尽管膜电位在两者的细胞生理学中起着中心作用 对于可兴奋和不可兴奋的细胞，我们对这些系统中的膜电位的理解仍然 不完整，很大程度上是由于缺乏研究高空间和高密度的细胞生理学的工具 时间分辨率。膜电位的测量依赖于高侵入性、低通量的直接测量 通过电极记录电压(膜片钳)或通过间接监测下游效应 通过成像(钙成像)检测膜电位。我们建议利用合成有机物质的力量 化学设计荧光电压传感器来探测神经元的膜电位动态和 除非兴奋性细胞外，还有心肌细胞。在一个互补的方法中，我们正在开发 基于小分子的活性集成器，随着时间的推移整合钙瞬变以实现高分辨率 在特定时间窗口内重建细胞活动-在长度尺度(超分辨率 显微镜、电子显微镜)，这是目前可用的传感器无法访问的。 尽管我们正在开发的许多工具在神经科学中都有应用，但这些策略和 这些技术可以应用于基础细胞生理学。另外，我的研究项目把 非常重视合成化学和分子设计，以实现我们的目标。我想我们会的 揭示与光致电子转移、超分子相关领域的基本见解 化学、物理有机化学和生物物理学，因为我们设计和开发这些新工具。

Abstract New Chemical Tools for Visualizing Cellular Physiology The cell membrane is the only organelle shared by all varieties of cellular life. Unequal distribution of ions and chemical species across the plasma membrane results in the generation of an electrochemical potential, and rapid changes in this membrane potential, or voltage, drive the unique physiology of excitable cells like neurons and cardiomyocytes. However, all cells, even non-excitable cells, possess a membrane potential, and mounting evidence supports a role for membrane potential in controlling fundamental cellular physiology—for example, cell cycle, migration, proliferation, and differentiation—in non-excitable cells. Despite the central role of membrane potential to the cellular physiology of both excitable and non-excitable cells, our understanding of membrane potential in these systems remains incomplete, due in large part to a lack of tools for studying cellular physiology with high spatial and temporal resolution. Measurements of membrane potential rely on highly invasive, low throughput direct voltage recording through electrodes (patch clamping) or by indirectly monitoring the down-stream effects of membrane potential via imaging (Ca2+ imaging). We propose to use the power of synthetic organic chemistry to design fluorescent voltage sensors to probe membrane potential dynamics in neurons and cardiomyocytes, in addition to non-excitable cells. In a complementary approach, we are developing small molecule-based activity integrators that integrate Ca2+ transients over time to enable high resolution reconstruction of cellular activity during a specified time window—at length scales (superresolution microscopy, electron microscopy) that are not accessible with currently available sensors. Although many of the tools we are developing have applications in neuroscience, these strategies and techniques can be applied to fundamental cellular physiology. Additionally, my research program places a heavy emphasis on synthetic chemistry and molecular design to achieve our goals. I anticipate we will uncover fundamental insights in areas related to photoinduced electron transfer, supramolecular chemistry, physical organic chemistry, and biophysics as we design and develop these new tools.