Genetics of Cocaine and Methamphetamine Sensitivity in Drosophila

项目摘要 非法使用可卡因和甲基苯丙胺等精神兴奋剂会造成巨大的社会经济成本 国际吧尽管我们对药物滥用的神经机制的理解有了进步， 和成瘾，对遗传风险因素知之甚少。人类遗传学研究令人困惑 遗传和环境异质性以及药物暴露的不受控制的变化。果蝇 melanogaster提出了一个强大的模型系统来研究药物敏感性的遗传基础， 因为遗传背景和环境，包括药物暴露，可以精确控制。许多 精神兴奋剂对人的作用在苍蝇中复制，并可能通过D. 黑胃多巴胺转运蛋白最近被结晶化，并被证明可以结合可卡因和 冰毒在这里，我们建议利用自然的遗传和表型变异在远交种 利用205个野生型玉米自交系群体构建了一个高代杂交群体。melanogaster 利用已测序和注释的基因组，D.黑腹遗传参考面板（DGRP），以 探索可卡因自愿消费变异背后的遗传结构， 冰毒我们将进行极端QTL定位和人工选择结合DNA， RNA测序作为两种互补的遗传作图策略来识别天然存在的变异体 影响可卡因和甲基苯丙胺的消费。我们将在DGRP中使用分离变异， 以及共同基因背景中的突变和RNAi构建体，以进行功能验证实验 候选基因和变异体在每种方法中被识别。我们将重点增加消费， 可卡因和甲基苯丙胺，因为消费是在DGRP遗传变量，我们以前 在控制条件下的食物消耗，初步数据显示，一些 DGRP系自愿消耗比4%蔗糖对照更大量的可卡因或甲基苯丙胺 解决方案，这表明有可能开发一个果蝇模型，用于与 成瘾本申请的具体目的是：（1）鉴定DGRP衍生的基因中的遗传变体。 与可卡因消费量增加有关的先进的交叉人口， 通过极端个体池的DNA测序使用极端QTL作图的甲基苯丙胺 和随机选择的对照组。(2)要创建针对与增加的 可卡因和甲基苯丙胺的消费通过长期的人工选择。(3)为在功能 验证与可卡因和甲基苯丙胺消费增加相关的变异和基因 具体目标1和2。 人类的直系同源物。R 我们 U01机制下的拟议实验结果将 将专注于测试进化上保守的候选基因， 召开一 丰富的新信息，可以指导未来的哺乳动物遗传学研究，包括人类。

PROJECT SUMMARY Illegal use of psychostimulants, such as cocaine and methamphetamine, incurs huge socioeconomic costs worldwide. Despite advances in our understanding of the neural mechanisms that mediate substance abuse and addiction, little is known about genetic risk factors. Genetic studies in human populations are confounded by genetic and environmental heterogeneity and uncontrolled variation in drug exposure. Drosophila melanogaster presents a powerful model system to study the genetic underpinnings of drug susceptibility, since the genetic background and environment, including exposure to drugs, can be controlled precisely. Many effects of psychostimulants on people are replicated in flies and are likely mediated through the D. melanogaster dopamine transporter, which has recently been crystallized and shown to bind cocaine and metamphetamine. Here, we propose to capitalize on natural genetic and phenotypic variation in an outbred advanced intercross population derived from a population of 205 inbred wild-derived lines of D. melanogaster with sequenced and well annotated genomes, the D. melanogaster Genetic Reference Panel (DGRP), to explore the genetic architectures that underlie variation in voluntary consumption of cocaine and methamphetamine. We will perform extreme QTL mapping and artificial selection combined with DNA and RNA sequencing as two complementary genetic mapping strategies to identify naturally occurring variants affecting consumption of cocaine and methamphetamine. We will use segregating variation in the DGRP as well as mutations and RNAi constructs in co-isogenic backgrounds to perform functional validation experiments of the candidate genes and variants identified in each approach. We will focus on increased consumption of cocaine and methamphetamine, since consumption is genetically variable in the DGRP, we have previously derived selection lines for food consumption under control conditions, and preliminary data show that some DGRP lines voluntarily consume larger amounts of cocaine or metamphetamine than a 4% sucrose control solution, suggesting it may be possible to develop a Drosophila model for complex behaviors related to addiction. The specific aims of this application are: (1) To identify genetic variants in a DGRP-derived advanced intercross population associated with increased consumption of cocaine and methamphetamine using extreme QTL mapping by DNA sequencing of pools of extreme individuals and randomly selected controls. (2) To create lines enriched for variants associated with increased consumption of cocaine and methamphetamine by long-term artificial selection. (3) To functionally validate variants and genes associated with increased consumption of cocaine and methamphetamine from Specific Aims 1 and 2. orthologs in humans. R We esults from the proposed experiments under the U01 mechanism will will focus on testing evolutionarily conserved candidate genes with culminate in a wealth of novel information that can guide future genetic studies in mammals, including humans.