Polymer-Free Nanosensors To Visualize Biochemical Dynamics in Dendritic Spines

无聚合物纳米传感器可视化树突棘生化动力学

• 批准号: 8660103
• 负责人: Heather A Clark
• 金额: $ 32.61万
• 依托单位: NORTHEASTERN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-06-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8660103
• 关键词: Acute; Adolescent; Affect; Biochemical; Calcium Chloride; Cell membrane; Cells; Cellular Structures; Charge; Dendritic Spines; Disease; Drug Formulations; Electrophysiology (science); Environment; Fluorescence; Foundations; Goals; Head; Image; Individual; Injection of therapeutic agent; Ions; Laser Scanning Microscopy; Ligands; Location; Mechanics; Methods; Monitor; Morphology; Mus; Neck; Neuraxis; Oils; Physiological; Polymers; Potassium; Preparation; Property; Role; Shapes; Signal Transduction; Slice; Sodium; Structure; Surface; Surface Properties; Synapses; Techniques; Temperature; Time; Vertebral column; design; hippocampal pyramidal neuron; insight; lipophilicity; nanosensors; novel; patch clamp; public health relevance; regenerative; research study; sensor; small molecule; two-photon

DESCRIPTION (provided by applicant): Dendritic spines are essential for integrating excitatory and inhibitory inputs in the central nervous system. The fine structure of the spines, with necks as small as 100 nm and heads as small as 400 nm, allow them to form ultra-structural compartments with localized control of signaling and biochemical microenvironment. The ultra-structure of spines does not readily allow for standard methods of characterization, such as confocal imaging and electrophysiology. Recent progress in two-photon and STED imaging has been essential to resolving structure and location, but obtaining insight to the biochemical environment remains elusive. Our goal is to use a novel Polymer-Free Nanosensors (PFN) combined with 2-photon laser scanning microscopy to characterize the biochemical environment of dendritic spines. Specifically, we propose assessing ion dynamics in the spines, starting with sodium and then easily extending the platform to other ions such as chloride, calcium, and potassium. Since loading nanosensors, even ones as small as 20 nm, through the necks of dendritic spines might prove difficult, we propose developing and characterizing a novel type of nanosensor: a polymer-less formulation that has the mechanical properties of an oil rather than a bead. This would allow us to load PFNs into even small structures, and then monitor fluorescence intensity as a real-time, reversible indicator of analyte concentration. Since the spine neck forms the barrier that diffusionally isolates the synapse, one predicts that these altered morphologies perturb the biochemical and electrical compartmentalization of the synapse and spine. Our proposal will determine the role of the spine neck in shaping synaptically-evoked signals and will set the foundation necessary for revealing the functional consequences of the morphological changes seen in disease states.

描述（由申请人提供）：树突状棘是在中枢神经系统中整合兴奋性和抑制性投入至关重要的。刺的精细结构，颈部小至100 nm，头小至400 nm，使它们可以形成具有信号传导和生化微环境的局部控制的超结构隔室。棘的超结构不容易允许标准的表征方法，例如共聚焦成像和电生理学。两光子和Sted成像的最新进展对于解决结构和位置至关重要，但是获得生化环境的见识仍然难以捉摸。我们的目标是使用新型的无聚合物纳米传感器（PFN）与2光子激光扫描显微镜相结合，以表征树突状棘的生化环境。具体而言，我们提出了评估棘中的离子动力学，从钠开始，然后轻松将平台扩展到其他离子，例如氯化物，钙和钾。由于加载纳米传感器，即使是小至20 nm的纳米传感器，也可能很难穿过树突状棘的颈部，因此我们建议开发和表征一种新型的纳米传感器类型：一种无聚合物的配方，具有油的机械性能，而不是珠子。这将使我们能够将PFN加载到小结构中，然后监测荧光强度作为实时，可逆的分析指标 专注。由于脊柱颈部形成了扩散分离突触的障碍，因此人们预测这些改变的形态会使突触和脊柱的生化和电隔室干扰。我们的建议将决定脊柱颈在塑造突触诱发的信号中的作用，并为揭示疾病状态中形态学变化的功能后果奠定了必要的基础。