Functional Characterization of synaptic calcium/calmodulin kinase II (CaMKII) acc

突触钙/钙调蛋白激酶 II (CaMKII) acc 的功能表征

• 批准号: 7938806
• 负责人: Jacqueline K Rose
• 金额: $ 39.19万
• 依托单位: WESTERN WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-01 至 2013-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7938806
• 关键词: 3-Dimensional; Address; Alzheimer' s Disease; Area; Ca(2+)-Calmodulin Dependent Protein Kinase; Calcium; Calmodulin; Cell Culture Techniques; Cell Death; Cell division; Cell physiology; Cells; Chemicals; Chemosensitization; Computer software; Coupled; Dendrites; Dendritic Spines; Devices; Disease; Epilepsy; Glutamate Receptor; Glutamates; Glycine; Goals; Hippocampus (Brain); Image; Immunofluorescence Immunologic; Investigation; Ischemia; Learning; Life; Long-Term Effects; Long-Term Potentiation; Measures; Memory; Methods; Microscope; Modification; Morphology; Myocardial Contraction; N-Methyl-D-Aspartate Receptors; Neuronal Plasticity; Neurons; Parkinson Disease; Phosphotransferases; Physiological Processes; Play; Process; Property; Proteins; Receptor Activation; Reporter; Reporting; Research; Role; Signal Transduction; Site; Staging; Stimulus; Stroke; Structure; Synapses; Synaptic Receptors; Synaptic plasticity; System; Time; Vertebral column; Work; carbohydrate metabolism; cellular imaging; density; design; interest; nervous system disorder; novel; public health relevance; reconstruction; stem

DESCRIPTION (provided by applicant): Calcium/calmodulin dependent kinase II (CaMKII) is widely expressed and activation of CaMKII plays a fundamental role in several cellular processes ranging from proper cell division and carbohydrate metabolism to synaptic plasticity and learning and memory (see Lisman et al., 2002 and Colomer and Means, 2007). The long-term goal of this research is to investigate the role of novel phenomenon called locally-induced propagating synaptic (L-IPS) translocation of calcium/calmodulin kinase II (CaMKII). This heterosynaptic process can be described as a slow, wave-like propagation of synaptic CaMKII accumulation that stems from localized application of glutamate and glycine to a small portion of dendrite, activating a subset of contiguous synapses. Within 10 minutes after this stimulation, CaMKII accumulates at synapses not only at the stimulation site but at synapses throughout the dendritic arbor. This process relies on NMDA receptor activation, L-type Ca2+ channels and results in an increase of expression of the AMPA-type glutamate receptor subunit GluR1 at synapses (~18% above baseline). Specific aims include: determining if heterosynaptic plasticity induced by synaptic accumulation following L-IPS translocation occludes long-term potentiation (LTP; a well-characterized proposed mechanism of synaptic plasticity). As well, investigation into expression levels of other synaptic proteins (e.g., GluR2, and NMDA receptor subunits) following L-IPS translocation of CaMKII will be conducted. The current research proposes studies to confirm stability and reversibility of synaptic CaMKII accumulation resulting from L-IPS translocation. Finally, changes in spine morphology will also be examined both during and at periods after L-IPS translocation of CaMKII. Live-cell imaging of reporter constructs expressed in dissociated hippocampal cell culture will be the predominate method employed to investigate these questions addressing the neuronal function of L-IPS translocation of CaMKII. The finding that local stimulation of a small dendrite area results in synaptic accumulation of CaMKII at non-stimulated synapses throughout the dendritic arbor alludes to a novel property of plasticity and intracellular signaling; thus, functional characterization of this process needs to be conducted. Several diseases implicate a role for CaMKII including Alzheimer's disease, epilepsy, Parkinson's disease and cell loss due to ischemia. Uncovering the role of this heterosynaptic phenomenon could elucidate further the dynamics of cell-wide CaMKII activation and provide possible avenues of discovery into the mechanisms of some of these disorders. PUBLIC HEALTH RELEVANCE: Calcium/calmodulin dependent kinase II (CaMKII) migrates to synapses throughout a neuron following stimulation of a small segment of dendrite. This locally-induced propagating synaptic (L-IPS) translocation of CaMKII requires further functional characterization to determine its role in neuron function. As CaMKII activation is involved in several physiological processes, ranging from myocardial contraction to synaptic plasticity, as well as neurological disorders like Alzheimer's, epilepsy and cell death due to stroke/ischemia, it is of interest to uncover why CaMKII signals activity from one local site to all the synapses of a neuron.

描述(申请人提供)：钙/钙调蛋白依赖的激酶II(CaMKII)广泛表达，激活CaMKII在从细胞正常分裂和碳水化合物代谢到突触可塑性和学习和记忆的几个细胞过程中发挥重要作用(见Lisman等人，2002和Columer and Means，2007)。本研究的长期目标是研究钙/钙调蛋白激酶II(CaMKII)的局部诱导传播性突触易位(L-IPS)这一新现象在其中的作用。这种异突触过程可以被描述为突触CaMKII积聚的缓慢波状传播，这种积聚源于谷氨酸和甘氨酸局部应用于树突的一小部分，激活了毗邻突触的一个子集。在刺激后的10分钟内，CaMKII不仅聚集在刺激部位的突触，而且聚集在整个树突的突触上。这一过程依赖于N-甲基-D-天冬氨酸受体的激活，L型钙通道，并导致突触处AMPA型谷氨酸受体亚单位GluR1的表达增加(比基线高出约18%)。具体目标包括：确定L-IPS易位后由突触堆积引起的异位突触可塑性是否阻断长时程增强(LTP；一个已被很好描述的突触可塑性机制)。此外，还将研究CaMKII在L-IPS易位后其他突触蛋白(如GluR2和Nmda受体亚单位)的表达水平。目前的研究提出了一些研究，以证实L-IPS易位导致突触CaMKII积聚的稳定性和可逆性。最后，还将检查在L-IPS易位CaMKII期间和之后脊柱形态的变化。在分离的海马细胞培养中表达的报告结构的活细胞成像将是研究这些问题的主要方法，以解决CaMKII的L-IPS易位的神经元功能。局部刺激小的树突区导致CaMKII在整个树突杆的非刺激突触处聚集，暗示了一种新的可塑性和细胞内信号传递的特性；因此，需要对这一过程进行功能表征。有几种疾病牵涉到CaMKII的作用，包括阿尔茨海默病、癫痫、帕金森病和由于缺血造成的细胞丢失。揭示这种异端突触现象的作用可以进一步阐明细胞范围内CaMKII激活的动力学，并为发现其中一些疾病的机制提供可能的途径。 与公共健康相关：钙/钙调蛋白依赖的激酶II(CaMKII)在刺激一小段树突后迁移到整个神经元的突触。这种局部诱导的传播性突触易位(L-IPS)需要进一步的功能鉴定来确定它在神经元功能中的作用。由于CaMKII激活涉及几个生理过程，从心肌收缩到突触可塑性，以及阿尔茨海默病、癫痫和中风/缺血导致的细胞死亡等神经系统疾病，因此有兴趣揭示为什么CaMKII从一个局部位置向神经元的所有突触发出信号。