Neuronal signal transduction in space and time using single quantum dots

使用单量子点进行空间和时间神经元信号转导

• 批准号: 8695500
• 负责人: Tothu Q Vu
• 金额: $ 33.27万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8695500
• 关键词: Address; Algorithms; Alzheimer' s Disease; Area; Behavior; Binding; Biochemical; Brain; Brain-Derived Neurotrophic Factor; Cause of Death; Cell membrane; Cells; Characteristics; Clinical; Complex; Cytoplasm; Data; Degenerative Disorder; Destinations; Development; Disease; Distant; Endocytosis; Endosomes; Event; Family; G-Protein-Coupled Receptors; Goals; Image; Imagery; Imaging Techniques; Imaging technology; Immunoblotting; Indium; Individual; Intracellular Transport; Investigation; Label; Learning; Life; Ligands; Location; MEKs; Maps; Masks; Memory; Molecular; Motion; Movement; Nerve Degeneration; Neuraxis; Neurodegenerative Disorders; Neurons; Neurotrophic Tyrosine Kinase Receptor Type 2; Parkinson Disease; Pathway interactions; Patients; Pattern; Pharmacologic Substance; Phosphorylation; Physiological; Play; Population Dynamics; Proteins; Psyche structure; Quantum Dots; Receptor Protein-Tyrosine Kinases; Receptor Signaling; Research; Research Personnel; Resolution; Role; Signal Pathway; Signal Transduction; Signal Transduction Pathway; Signaling Molecule; Signaling Protein; Site; Societies; Surface; Synaptic plasticity; Techniques; Technology; Testing; Time; base; clinically relevant; disability; effective therapy; fluorophore; immunocytochemistry; improved; nanoparticle; nanoscale; neural growth; neuronal growth; novel; receptor; relating to nervous system; response; single molecule; spatial relationship; spatiotemporal; success; therapeutic target; time use; treatment strategy

DESCRIPTION (provided by applicant): The long-term goal of the proposed research is to understand how neurons transduce biochemical signals in space and time, at the molecular level. Brain-derived neurotrophic factor (BDNF) is highly expressed in the brain and activates critical receptor signaling pathways that dictate neuronal growth, synaptic plasticity, and memory. Decreased BDNF signaling is a key element in devastating neurodegenerative diseases, including Alzheimer's disease. Thus, BDNF signaling transduction pathways are attractive therapeutic targets. However, despite the important role of BDNF in the brain, mechanisms underlying BDNF signaling in the central nervous system are not well understood. Signaling complexes consisting of internalized BDNF receptors (BDNF-Rs) are hypothesized to represent a fundamental mechanism for propagating BDNF signaling. Unfortunately, understanding of these mechanisms- how BDNF-Rs move in space and time in neurons, and how BDNF-R spatiotemporal dynamics regulate downstream signaling events- remains poorly defined. We have recently shown that fluorescent nanoparticle quantum dots allow real-time, intracellular visualization of individual receptor complexes with nanoscale spatial resolution, thereby providing the first access to dynamic populations of individual BDNF- Rs previously invisible to more conventional imaging techniques. Accordingly, we propose to expand current single quantum dot (QD) imaging technologies to create novel, ultra-sensitive, and photostable QD probes capable of high-resolution imaging of the spatiotemporal behavior of single neuronal receptor complexes inside live cells. These capabilities will be applied to elucidate the spatiotemporal action of BDNF-R mechanisms in regulating downstream signaling pathways implicated in neurodegenerative diseases. We propose to develop new BDNF-QD probes and validate new algorithms for tracking and analyzing spatiotemporal BDNF signaling with single molecule sensitivity. We will: (1) identify the optimal monovalent QD bioconjugation strategy for physiological tracking of individual receptor signaling complexes within cells; (2) establish QD algorithms to track and analyze individual BDNF receptor complexes in neurons; (3) determine the role of BDNF-receptor complexes in propagating downstream cellular signaling. As BDNF-Rs belong to the family of tyrosine kinase receptors that, along with G-protein coupled receptors, make up 50% of all pharmaceutical targets, the technologies developed here will be relevant to other disease states in which impaired receptor signaling may play an important role.

描述（由申请人提供）：拟议研究的长期目标是了解神经元如何在分子水平上在空间和时间上转导生化信号。 脑源性神经营养因子 (BDNF) 在大脑中高度表达，并激活决定神经元生长、突触可塑性和记忆的关键受体信号传导通路。 BDNF 信号传导减少是导致阿尔茨海默病等毁灭性神经退行性疾病的关键因素。 因此，BDNF信号转导途径是有吸引力的治疗靶点。 然而，尽管 BDNF 在大脑中发挥着重要作用，但中枢神经系统中 BDNF 信号传导的机制尚不清楚。 假设由内化 BDNF 受体 (BDNF-R) 组成的信号复合物代表了传播 BDNF 信号的基本机制。 不幸的是，对这些机制——BDNF-R如何在神经元中在空间和时间上移动，以及BDNF-R时空动力学如何调节下游信号事件——的理解仍然不明确。 我们最近表明，荧光纳米颗粒量子点允许以纳米级空间分辨率对单个受体复合物进行实时、细胞内可视化，从而首次提供了以前用更传统的成像技术无法看到的单个 BDNF-R 的动态群体。 因此，我们建议扩展当前的单量子点（QD）成像技术，以创建新颖的、超灵敏且光稳定的QD探针，能够对活细胞内单个神经元受体复合物的时空行为进行高分辨率成像。 这些能力将用于阐明 BDNF-R 机制在调节与神经退行性疾病相关的下游信号通路中的时空作用。 我们建议开发新的 BDNF-QD 探针并验证新算法，以单分子灵敏度跟踪和分析时空 BDNF 信号传导。 我们将：（1）确定最佳的单价量子点生物共轭策略，用于细胞内单个受体信号复合物的生理追踪； （2）建立QD算法来跟踪和分析神经元中单个BDNF受体复合物； (3)确定BDNF-受体复合物在传播下游细胞信号传导中的作用。 由于 BDNF-R 属于酪氨酸激酶受体家族，该家族与 G 蛋白偶联受体一起构成了所有药物靶标的 50%，因此这里开发的技术将与受体信号传导受损可能发挥重要作用的其他疾病状态相关。