Genetics of Cocaine and Methamphetamine Sensitivity in Drosophila

项目总结 非法使用精神刺激剂，如可卡因和甲基苯丙胺，造成巨大的社会经济代价。 全世界。尽管我们对调节物质滥用的神经机制的理解取得了进展 而成瘾，人们对遗传风险因素知之甚少。在人类群体中的基因研究是混乱的 由于遗传和环境的异质性以及药物暴露的不受控制的变异。果蝇 Blackogaster提供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，包括接触药物，是可以精确控制的。许多 心理刺激剂对人的影响在果蝇身上复制，并可能通过D。 黑素胃多巴胺转运蛋白，最近被结晶并被证明与可卡因和 甲基苯丙胺。在这里，我们建议利用近交系的自然遗传和表型变异。 来自205个野生黑腹金龟自交系的先进杂交群体 有了测序和良好注释的基因组，D.Blackogaster遗传参考小组(DGRP)，到 探索自愿消费可卡因和可卡因的遗传结构 冰毒。我们将结合DNA和DNA进行极端QTL定位和人工选择 RNA测序作为两种互补的遗传作图策略识别自然发生的变异体 影响可卡因和甲基苯丙胺的消费。我们将使用DGRP中的分离变量作为 以及共等基因背景中的突变和RNAi构建，以执行功能验证实验 每种方法中确定的候选基因和变种的数量。我们将重点增加消费。 可卡因和甲基苯丙胺，因为在DGRP中消费是遗传变量，我们以前 导出了控制条件下的食物消费选择系，初步数据表明，一些 与4%蔗糖对照相比，DGRP品系自愿消耗更多的可卡因或甲苯丙胺 解决方案，这表明有可能开发一种果蝇模型，以研究与 上瘾。本申请的具体目的是：(1)识别DGRP来源的遗传变异 与可卡因和可卡因消费增加相关的高级杂交种群 甲基苯丙胺极端个体群体DNA测序的极端QTL定位 和随机选择的控件。(2)为与增加关联的变体创建丰富的行 通过长期的人为选择消费可卡因和冰毒。(3)从功能上讲 验证与可卡因和甲基苯丙胺消费增加相关的变异和基因 来自具体目标1和2。 人类的同源基因。R 我们 在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 最终以一种 丰富的新信息，可以指导未来的哺乳动物，包括人类的基因研究。

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.