Quantitative mapping of molecules and release properties at nerve terminals

神经末梢分子和释放特性的定量图谱

• 批准号: 8825287
• 负责人: Timothy Aidan Ryan
• 金额: $ 46.66万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-12-02 至 2019-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8825287
• 关键词: Ablation; Action Potentials; Area; Back; Beryllium; Binding; Biological; Brain; Calcium; Calcium Channel; Cell membrane; Cells; Chemical Synapse; Chemicals; Communication; DNA Sequence Alteration; Dependence; Disease; Emerging Technologies; Ensure; Environment; Epitopes; Equilibrium; Exocytosis; Functional disorder; Future; Genetic; Goals; Human; Kinetics; Lead; Link; Maps; Measures; Mediating; Membrane Protein Traffic; Migraine; Molecular; Nerve; Neurons; Neurotransmitters; Optical Methods; P-Q type voltage-dependent calcium channel; PHluorin; Parkinson Disease; Performance; Physiological; Play; Potassium Channel; Process; Property; Proteins; Recycling; Regulation; Role; Schizophrenia; Shapes; Signal Transduction; Site; Stimulus; Surface; Synapses; Synaptic Transmission; Synaptic Vesicles; Time; Vesicle; Work; base; neurotransmitter release; new technology; novel; novel strategies; presynaptic; public health relevance; release of sequestered calcium ion into cytoplasm; research study; residence; response; success; synaptic function; trafficking; voltage

DESCRIPTION (provided by applicant): Information flow in the brain is mediated by transduction of electrical information into chemical information and back again at chemical synapses. Synapses are made up of crucial cellular machineries that orchestrate a balance of membrane traffic to and from the plasma membrane. Our goal is to develop detailed quantitative understanding of the synapse both in terms of physiological responses to action potential stimuli as well as the molecular underpinnings of its function. One of the most important functional elements is the voltage-gated calcium channel as it converts the electrical signal into a flux of calcium that drives neurotransmitter release in a highly non-linear fashion. We recently developed sensitive approaches that allow us to characterize key properties of these channels and the electrical signal that controls them in their native environment, the nerve terminal. The goal of this project is determine the molecular basis of key mechanisms that determine VGCC function. The first aim will examine the mechanisms of a novel form of adaptive plasticity whereby changes in VGCC number at nerve terminals in turn changes the shape of the electrical signal (the action potential). These experiments make use of an emerging technology of genetically-encoded fluorescent voltage indicators that allow one to quantitatively measure the action potential waveform in the nerve terminal and how it is controlled. Our second Aim will use another new technology allowing us to determine how long VGCCs typically stay resident in the active zone, whether they can recycle through an intracellular presynaptic compartment and how these dynamics are controlled by activity, calcium influx and a number of presynaptic proteins. The third Aim will examine how different active zone proteins, in particular Munc13 and Rim1, control different functional and cell biological aspects of VGCC function at nerve terminals.

描述（由申请人提供）：大脑中的信息流是通过将电信息转换成化学信息并在化学突触处再次转换回来来介导的。突触由重要的细胞机制组成，这些机制协调了进出质膜的膜交通平衡。我们的目标是从对动作电位刺激的生理反应以及其功能的分子基础两方面对突触进行详细的定量了解。最重要的功能元件之一是电压门控钙通道，因为它将电信号转化为钙流，以高度非线性的方式驱动神经递质释放。我们最近开发了敏感的方法，使我们能够表征这些通道的关键特性以及在其天然环境（神经末梢）中控制它们的电信号。该项目的目标是确定决定VGCC功能的关键机制的分子基础。第一个目标将研究一种新形式的适应性可塑性的机制，即神经末梢VGCC数量的变化反过来改变电信号（动作电位）的形状。这些实验利用了一种新兴的基因编码荧光电压指示器技术，可以定量测量神经末梢的动作电位波形及其控制方式。我们的第二个目标将使用另一种新技术，使我们能够确定VGCC通常在活动区停留多长时间，它们是否可以通过细胞内突触前区室进行再循环，以及这些动力学如何受到活动，钙内流和许多突触前蛋白的控制。第三个目标将研究不同的活性区蛋白，特别是Munc13和Rim1，如何控制不同的功能和细胞生物学方面的VGCC功能在神经末梢。