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大脑回路的进行性失调，大脑回路负责奖励、压力和动机。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意想不到的可塑性程度，并表明由于组蛋白调节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，组蛋白修饰在学习和记忆等过程以及滥用药物的影响中成为潜在的参与者。因此，本研究的假设是，在大脑中负责奖励、压力和动机的区域中，长期的翻译后组蛋白修饰是导致过度饮酒的神经适应的关键。为了验证这一假设，本研究将对酒精依赖引起的特定激活和抑制组蛋白标记的变化进行全基因组调查：1)慢性间歇性暴露（CIE），这是在整个INIA联盟中提出的依赖相关饮酒增加的范例；2)操纵G蛋白β 1亚基水平的小鼠(0(31)，该亚基被INIA联盟鉴定为酒精饮用的调节剂，可以直接调节染色质动力学。然后，我们将扩展组蛋白修饰在差异调节基因上的研究，以确定与染色质状态相关的其他组蛋白标记，以确定过量饮酒特征的组蛋白修饰库。最后，我们将通过生化、形态和行为策略验证在差异调节基因上观察到的组蛋白修饰模式的功能意义。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（ChlP-Chip）或定量实时PCR （ChlP-PCR）。数据将与INIA联盟产生的基因表达、行为和药理学数据整合。该项目的结果将有助于为过度饮酒的神经生物学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