Genetic and Transcriptomic Mechanisms of Progressive Ethanol Consumption in the Diversity Outbred Mouse

项目摘要 酒精使用障碍（AUD）构成了全球医疗保健负担，具有显著的发病率和 死亡率与过量饮酒有关，仍然缺乏有效的治疗选择。人类 全基因组关联研究最近已经鉴定了潜在地调节酒精消耗的基因， 但确定它们的作用机制仍然很困难。影响基因表达的遗传变异 被认为是AUD的一个附加因素，但由于混杂因素，仍难以在人体中进行研究 环境因素、组织收集困难和不能进行机械操作。 小鼠模型是一种有效的替代品;来自杰克逊实验室的多样性远交（DO）小鼠显示出大的 数量的遗传多样性和小的重组间隔，允许精确定位的数量 性状基因座（QTL）。我们实验室最近使用多样性远交（DO）小鼠的研究发现， 乙醇消耗量，DO小鼠的乙醇摄入量呈渐进式，遗传性范围 48 - 62%。多个高度显著或暗示的行为数量性状基因座（bQTL）被确定， 酒精消耗表型，沿着独特的位置候选基因;然而， 因果候选人和特定基因影响乙醇消耗的机制的定义 尚未完成。我们假设DO小鼠乙醇消耗的遗传机制 变异主要是由PFC和NAc基因表达网络中的同源差异驱动的， 结合行为和表达遗传学方法可以确定关键的分子机制， 调节乙醇消耗的候选基因。为了验证这一假设，我们的目标是：1）采用一种算法， 使用从PFC和NAc收集的RNA-seq数据对影响乙醇消耗的候选基因进行排名 来自DO小鼠的样本，并在功能上表征与乙醇相关的基因表达网络 消费; 2）得出关于个体基因表达模式及其 与乙醇消耗的关系，并估计直接遗传和个体基因转录介导 使用结构方程模型的影响;以及3）使用病毒载体小鼠遗传学验证因果候选物 调节乙醇消耗的候选基因。这些研究将为申请人提供强大的 在定量遗传学，基因组学和转录组学分析，以及神经生物学的独特培训， 酒精，为他未来作为行为遗传学的独立调查员的成功职业生涯做好准备。 酒精

Project Abstract Alcohol use disorder (AUD) poses a global healthcare burden, with significant morbidity and mortality associated with excessive alcohol consumption and effective therapeutic options still lacking. Human genome-wide association studies have recently identified genes potentially modulating alcohol consumption, but pinpointing their mechanisms of action remains difficult. Genetic variance influencing gene expression has been suggested as an additional factor in AUD but remains difficult to study in humans due to confounding environmental factors, difficulty with tissue collection and inability to conduct mechanistic manipulations. Mouse models are an effective substitute; Diversity Outbred (DO) mice from Jackson Labs display a large amount of genetic diversity and small recombination intervals, allowing for precision mapping of quantitative trait loci (QTLs). Recent research in our lab using Diversity Outbred (DO) mice identified marked variability in ethanol consumption, with a pattern of progressive ethanol intake across the DO mice and heritability ranging from 48-62%. Multiple highly significant or suggestive behavioral quantitative trait loci (bQTL) were identified for alcohol consumption phenotypes, along with unique positional candidate genes; however, determination of causal candidates and definition of mechanisms by which specific genes influence ethanol consumption have not been yet been accomplished. We hypothesize that genetic mechanisms of DO mouse ethanol consumption variance are largely driven by cognate differences in gene expression networks across PFC and NAc and that a combined behavioral and expression genetics approach can identify critical molecular mechanisms and candidate genes modulating ethanol consumption. To test this hypothesis, we aim to 1) employ an algorithm to rank candidate genes influencing ethanol consumption using RNA-seq data collected from PFC and NAc samples from DO mice, and functionally characterize gene expression networks associated with ethanol consumption; 2) derive mechanistic causal inferences about individual gene expression patterns and their relationships with ethanol consumption, and estimate direct genetic and individual gene transcript mediation effects using structural equation modeling; and 3) validate causal candidates using viral vector mouse genetic modulation of a candidate gene for ethanol consumption. These studies will provide the applicant with robust and unique training in quantitative genetics, genomic and transcriptomic analyses, and the neurobiology of alcohol, preparing him for a successful career as future independent investigator in the behavioral genetics of alcohol.