CRCNS: Spatial & Temporal Aspects of cAMP/PKA Signaling Underlying Information

描述（由申请人提供）：海马体内神经元对特定时间和空间刺激模式的差异反应能力是神经回路中记忆和信息存储的基础。信号转导通路对信息存储至关重要，关键信号分子的改变，如camp依赖性蛋白激酶（PKA）信号通路，改变了海马依赖性学习和一种被称为长期增强（L-LTP）的突触可塑性形式。这些信号通路的改变在酒精中毒、抑郁症、精神分裂症和阿尔茨海默病等神经和精神疾病中起着关键作用。尽管具有临床意义，但对于信号通路如何对突触输入的不同时间和空间模式做出不同的反应，我们知之甚少。通过a激酶锚定蛋白（AKAPs）将PKA定位到亚细胞区室的动力学为这种空间和时间特异性提供了一种潜在的机制。我们提出了一套创新和变革性的实验来研究涉及PKA和akap的多蛋白复合物在神经元信息存储和突触可塑性中的关键作用。具体目标1。确定蛋白激酶A （PKA）在后期长期增强（L-LTP）的时间敏感性中的作用。利用荧光成像、电生理、生物化学和计算模型测量LTP诱导刺激后cAMP和PKA的活性水平。这些综合实验和建模将评估NMDA和D1受体信号在突触可塑性的长期形式中的作用，并将评估这些受体激活的信号通路之间相互作用的时间敏感性。具体目标2。确定海马神经元诱导L-LTP的生化信号机制的空间特异性。计算模型、荧光成像和电生理学方法将被用来测量在PKA锚定抑制剂存在或不存在的情况下，L-LTP和cAMP和PKA活性梯度。这项研究的成功完成将为研究这一通路的改变如何导致精神分裂症和酒精中毒等精神疾病奠定基础。

DESCRIPTION (provided by applicant): The ability of neurons within the hippocampus to differentially respond to specific temporal and spatial patterns of stimulation underlies the storage of memory and information in neural circuits. Signal transduction pathways are critical for information storage, and alterations in key signaling molecules, such as the cAMP-dependent protein kinase (PKA) signaling pathway, modify both hippocampus-dependent learning and a form of synaptic plasticity known as long-term potentiation (L-LTP). Alterations in these signaling pathways play a critical role in neurological and psychiatric disorders such as alcoholism, depression, schizophrenia and Alzheimer's disease. Despite this clinical relevance, little is known about how signaling pathways respond differentially to distinct temporal and spatial patterns of synaptic input. The dynamics of PKA localization to subcellular compartments by A-Kinase Anchoring Proteins (AKAPs) provides a potential mechanism for such spatial and temporal specificity. We propose an innovative and transformative set of experiments to investigate the critical role of multi-protein complexes involving PKA and AKAPs in neuronal information storage and synaptic plasticity. SPECIFIC AIM 1. Define the role of protein kinase A (PKA) in the temporal sensitivity of late phase long-term potentiation (L-LTP). Fluorescent imaging, electrophysiology, biochemistry and computational modeling will be utilized to measure the level of cAMP and PKA activity after LTP inducing stimuli. These integrated experiments and modeling will evaluate the role of NMDA and D1 receptor signaling in long-lasting forms of synaptic plasticity, and will evaluate the temporal sensitivity of interactions between signaling pathways activated by these receptors. SPECIFIC AIM 2. Define the spatial specificity of biochemical signaling mechanisms underlying L-LTP induction in hippocampal neurons. Computational modeling, fluorescent imaging and electrophysiology approaches will be utilized to measure L-LTP and gradients of cAMP and PKA activity in the presence or absence of inhibitors of PKA anchoring. Successful completion of the research will form the basis for investigating how alterations in this pathway contributes to psychiatric disease such as schizophrenia and alcoholism.