MOLECULAR MECHANISMS OF PROENKEPHALIN GENE REGULATION

脑啡肽原基因调控的分子机制

• 批准号: 2116000
• 负责人: MICHAEL J COMB
• 金额: $ 7.57万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-07-01 至 1995-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2116000
• 关键词: DNA footprinting; behavioral genetics; biological signal transduction; calcium flux; enkephalins; gene expression; genetic enhancer element; genetic regulation; genetic transcription; laboratory mouse; molecular cloning; neural transmission; nucleic acid probes; nucleoproteins; oxidative phosphorylation; phorbols; polymerase chain reaction; protein kinase; protein purification; protein sequence; protein structure function; second messengers; site directed mutagenesis; synapses; tissue /cell culture; transcription factor; transfection

My long range goals are to develop an understanding of how neural activity regulates gene expression, and to ultimately understand how these processes contribute to environmental and drug induced stable/adaptive changes in the nervous system. A better understanding of theses processes will help us understand the adaptive physiologic changes underlying drug addiction, tolerance, withdrawal, and drug-seeking behaviors. The molecular mechanisms underlying learning, memory, long-term effects of addictive drugs, and other stable/adaptive changes in the nervous system are largely unknown. With the discovery that neurons transduce environmental inputs into changes in gene expression, the hypothesis has emerged that trans-synaptic regulation of gene expression may induce the biochemical changes underlying many forms of neural signaling plasticity. To understand these processes it is necessary to identify both the pathways and mechanisms mediating the effects of learning, psychotropic drugs, and other synaptically mediated processes on gene expression. Neural regulation of the opioid precursor, proenkephalin, is an excellent model system to study mechanisms underlying synaptic regulation of gene expression because: i) transcription is both activated and repressed by synaptic signals, ii) in the brain, events such as electrical stimulation which induce LTP also induce dramatic and long lasting changes in proenkephalin gene expression, iii) the gene products, enkephalins, are important signaling molecules regulating diverse neural pathways including analgesia, reward and motivational states, and hormone release. The primary objective of this research proposal is to identify and characterize nucleoprotein complexes which regulate proenkephalin gene expression and to determine how these nucleoprotein complexes mediate synaptic regulation of proenkephalin transcription via their interaction with a well characterized second messenger inducible DNA enhancer. In the period covered by this proposal, studies will focus on defining components of ENKTF-1 and Fos/Jun nucleoprotein complexes which mediate synaptic regulation of proenkephalin transcription. In addition their functional and biochemical interactions with the proenkephalin inducible DNA enhancer and signals transmitted through intracellular signaling pathways will be investigated. Because the transcription factors described above are activated by both neurotransmitters and pharmacologic agents they can be considered to be important targets of drug action. Progress in understanding these mechanisms should provide insight into the pathogenesis and treatment of many disorders affecting the nervous system.

我的长期目标是了解神经活动如何 调节基因表达，并最终了解这些过程是如何进行的 有助于环境和药物引起的稳定/适应性变化 神经系统。 更好地理解这些过程将有助于我们 了解药物成瘾背后的适应性生理变化， 耐受、戒断和寻求药物行为。 学习、记忆、长期影响的分子机制 成瘾药物以及神经系统的其他稳定/适应性变化 很大程度上是未知的。 随着神经元传导的发现 环境输入影响基因表达的变化，该假设 发现基因表达的跨突触调节可能诱导 多种形式的神经信号可塑性背后的生化变化。 要理解这些过程，有必要确定这两个途径 以及介导学习、精神药物和精神药物影响的机制 其他突触介导的基因表达过程。 神经 阿片类药物前体脑啡肽原的调节是一个很好的模型 研究基因突触调控机制的系统 表达，因为： i) 转录既被激活又被抑制 突触信号，ii) 大脑中的事件，例如电刺激 诱导 LTP 的同时也会引起显着且持久的变化 脑啡肽原基因表达，iii) 基因产物，脑啡肽，是 调节多种神经通路的重要信号分子，包括 镇痛、奖励和动机状态以及激素释放。 这 本研究计划的主要目标是确定和表征 调节脑啡肽原基因表达的核蛋白复合物 确定这些核蛋白复合物如何介导突触调节 脑啡肽原通过与已充分表征的相互作用进行转录 第二信使诱导型 DNA 增强子。 在此期间内 提案，研究将集中于定义 ENKTF-1 和 Fos/Jun 的组成部分 介导脑啡肽原突触调节的核蛋白复合物 转录。 此外，它们的功能和生化相互作用 具有脑啡肽原诱导型 DNA 增强剂和信号传输 将通过细胞内信号传导途径进行研究。 因为 上述转录因子由两者激活 神经递质和药物制剂，它们可以被认为是 药物作用的重要靶点。 在理解这些方面取得进展 机制应提供对发病机制和治疗的深入了解 许多影响神经系统的疾病。