Neurotrophic Factor & Neuronal Primary Responses Genes

神经营养因子

• 批准号: 6612735
• 负责人: Harvey R. Herschman
• 金额: $ 34.31万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-08-06 至 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6612735
• 关键词: PC12 cells; antisense nucleic acid; cAMP response element binding protein; cell differentiation; electrophysiology; exocytosis; ganglion cell; gene expression; gene induction /repression; gene targeting; genetically modified animals; hippocampus; laboratory mouse; mitogen activated protein kinase; neural plasticity; neurobiology; neurons; neurotrophic factors; oligonucleotides; protein structure function; regulatory gene; synaptic vesicles; synaptotagmin; transcription factor; urokinase

DESCRIPTION (From the Applicant's Abstract): We have two goals in our neurobiological studies. Our first goal has been to identify, in neurons, depolarization-induced immediate-early genes (IEGs) that play a role in synaptic plasticity and to characterize the biochemical mechanisms by which these IEGs mediate synaptic function. Our second goal has been to identify, in neuronal precursors, IEGs induced preferentially by Nerve Growth Factor (NGF) versus other stimulating ligands and to characterize the biochemical mechanisms by which these NGF-induced IEGs mediate NGF-driven neuronal differentiation. We identified synaptotagmin IV (Syt IV) as an IEG induced by depolarization in the hippocampus, prepared anti-Syt IV antibodies and showed that Syt IV is a labile protein incorporated into synaptic vesicles after induced synthesis, where it can form oligomers with Syt I. We created a Syt IV knock-out mouse, and demonstrated that Syt IV (-/-) mice are deficient in acquiring two hippocampal-dependent learning tasks, but not in acquiring two amygdala-associated learning tasks. We subsequently identified four protein kinases (KID-l, PIM-1, SIK, MAPKAP-2) and two transcription factors (nurr1, rTLE3) induced by depolarization. These genes are additional candidate IEGs whose products may mediate synaptic plasticity. We also identified six messages preferentially induced by NGF (versus Epidermal Growth Factor) in the PC12 cell model system of neuronal differentiation. We demonstrated that one of these IEGs, the urokinase plasminogen activator receptor (UPAR), is required for NGF-driven PC12 cell morphological differentiation and secondary response gene expression, using UPAR antisense oligonucleotides and anti-UPAR antibody. We will determine the biochemical basis for Syt IV modulation of synaptic function and collaborate on studies of electrophysiological correlates of the Syt IV (-/-) behavioral deficits. We will determine if Syt IV and our depolarization-induced IEGs are induced via the CREB pathway, and whether they modulate depolarization-induced, calcium-dependent exocytosis. For those IEGs that appear to be good candidates for modulators of synaptic function, we will prepare knock-out mice and analyze their behavioral characteristics. To determine the role of UPAR in NGF-driven neuronal maturation, we will examine development of sympathetic and sensory ganglia in UPAR null mice. We will also use cultured peripheral ganglion cells from BAX/NGF null mice to characterize the role of UPAR in NGF-driven differentiation. Finally, we will determine mechanisms by which (i) NGF induces UPAR and (ii) UPAR modulates NGF-driven neuron differentiation.

描述（来自申请人的摘要）：在我们的研究中，我们有两个目标。 神经生物学研究。我们的第一个目标是在神经元中， 去极化诱导的立即早期基因（IEGs），在 突触可塑性，并表征生物化学机制， 这些IEG介导突触功能。我们的第二个目标是确定， 神经元前体细胞，神经生长因子（NGF）优先诱导的IEG 与其他刺激配体，并表征生化机制 这些NGF诱导的IEG通过其介导NGF驱动的神经元分化。 我们鉴定了突触结合蛋白IV（Syt IV）作为一种由去极化诱导的IEG， 海马，制备抗Syt IV抗体，并显示Syt IV是一种 在诱导合成后掺入突触囊泡的不稳定蛋白质， 在那里它可以与Syt I形成低聚物。我们制造了一只Syt IV基因敲除小鼠 并证明了Syt IV（-/-）小鼠在获得两个 依赖于营地的学习任务，但不是在获得两个 杏仁核相关的学习任务。我们随后鉴定了四种蛋白质 激酶（KID-1，PIM-1，SIG，MAPKAP-2）和两种转录因子（nurr 1， rTLE3）。这些基因是额外的候选IEGs 其产物可介导突触可塑性。 我们还确定了六个信息优先诱导的神经生长因子（相对于表皮 生长因子）在PC 12细胞模型系统中的神经元分化。我们 证明了其中一种IEGs，尿激酶纤溶酶原激活剂， 受体（UPAR），是NGF驱动的PC 12细胞形态学所必需的 分化和次级应答基因表达，使用UPAR反义 寡核苷酸和抗UPAR抗体。 我们将确定Syt IV调节突触的生物化学基础， 功能和合作研究的电生理相关的 Syt IV（-/-）行为缺陷。我们将确定Syt IV和我们的 去极化诱导的IEGs是通过CREB途径诱导的，以及它们是否 调节去极化诱导的钙依赖性胞吐作用。对于这些IEGs 似乎是突触功能调节剂的良好候选者，我们将 制备基因敲除小鼠并分析其行为特征。 为了确定UPAR在NGF驱动的神经元成熟中的作用，我们将 检查UPAR敲除小鼠中交感神经节和感觉神经节的发育。我们 还将使用来自BAX/NGF缺失小鼠的培养的外周神经节细胞， 表征UPAR在NGF驱动的分化中的作用。最后我们将 确定（i）NGF诱导UPAR和（ii）UPAR调节 NGF驱动的神经元分化。