Histone modifications in transcriptional regulation by alcohol dependence

描述（由申请人提供）：强迫性（依赖性）酒精摄入背后的神经生物学机制涉及促进奖励、压力和动机的大脑回路的进行性失调。虽然组蛋白修饰在历史上被认为是静态的，但越来越多的证据揭示了一种意想不到的可塑性程度，并表明由于组蛋白调控改变而导致的基因表达的长期变化原则上可能是可逆的。在有丝分裂后的神经元中，组蛋白修饰正在成为学习和记忆以及滥用药物影响等过程的潜在参与者。因此，在本提案中测试的假设是，大脑区域中有利于奖励，压力和动机的持久翻译后组蛋白修饰是过度饮酒的神经适应的关键。为了验证这一假设，本研究将在全基因组范围内对酒精依赖诱导的选定激活和抑制组蛋白标记的变化进行研究：1）慢性间歇性暴露（CIE），INIA联盟提出的依赖相关饮酒增加的范例;和2）操纵G蛋白β 1亚基（0（31））水平的小鼠，其被INIA协会鉴定为可以直接调节染色质动力学的饮酒调节剂。然后，我们将扩大组蛋白修饰的差异调节基因的研究，确定与染色质状态相关的其他组蛋白标记，以定义组蛋白修饰的剧目，其特征是过量饮酒。最后，我们将验证组蛋白修饰模式的功能意义，观察到的差异调节基因与生化，形态和行为策略。对于整个基因组和特定基因的组蛋白修饰的定位和定量，我们将分别使用染色质免疫沉淀结合平铺阵列（ChIP-Chip）或定量真实的时间PCR（ChIP-PCR）。数据将与INIA联盟产生的基因表达、行为和药理学数据相结合。该项目的结果将有助于为过度饮酒的神经生物学的综合系统生物学分析奠定基础

DESCRIPTION (provided by applicant): The neurobiological mechanisms behind compulsive (dependent) alcohol intake involve a progressive dysregulation of brain circuits that subserve reward, stress and motivation. While histone modifications were historically considered static, mounting evidence is revealing an unexpected degree of plasticity and suggests that long-lasting changes in gene expression due to altered histone regulation may, in principle, be reversible. In post-mitotic neurons, histone modifications are emerging as potential players in processes like learning and memory and the effects of drugs of abuse. Thus, the hypothesis under test in the present proposal is that long-lasting post-translational histone modifications in brain regions that subserve reward, stress and motivation are key to the neuroadaptations that underlie excessive alcohol consumption. To test this hypothesis, the present proposal will conduct a genome-wide investigation of changes of selected activation and repression histone marks induced by alcohol dependence in 1) chronic intermittent exposure (CIE), a paradigm of dependence-associated increased drinking that is proposed throughout the INIA consortium; and 2) mice with manipulation of the level of the G protein beta 1 subunit (0(31), which was identified by the INIA consortium as a regulator of alcohol drinking that can directly regulate chromatin dynamics. We will then expand the investigation of histone modifications at the differentially regulated genes identified to additional histone marks associated with chromatin states to define the repertoire of histone modifications that characterizes excessive alcohol intake. Lastly, we will validate the functional significance of the patterns of histone modifications observed at the differentially regulated genes with biochemical, morphological and behavioral strategies. For the mapping and quantitation of histone modifications across the genome and at specific genes, we will use chromatin immunoprecipitation coupled with tiling arrays (ChlP-Chip) or quantitative real time PCR (ChlP-PCR), respectively. Data will be integrated with gene expression, behavioral and pharmacological data generated across the INIA consortium. The results of this project will contribute to lay the foundation for an integrated systems biology analysis of the neurobiology of excessive alcohol consumption