Identification of gene variants mediating the behavioral and physiological response to THC

鉴定介导 THC 行为和生理反应的基因变异

• 批准号: 10660808
• 负责人: Bob Mack Moore
• 金额: $ 75.8万
• 依托单位: UNIVERSITY OF TENNESSEE HEALTH SCI CTR
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2028-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10660808
• 关键词: Absence of pain sensation; Accounting; Acute; Address; Alleles; American; Attitude; Behavior; Behavioral; Biological; Brain; Brain region; CNR1 gene; Candidate Disease Gene; Cannabinoids; Cannabis; Chromosome Mapping; Complex; Consumption; Corpus striatum structure; Data; Dose; Exposure to; Female; Genes; Genetic; Genetic Engineering; Genetic Variation; Genomics; Genotype; Goals; Health; Heritability; Human; Hybrids; Inbred Mouse; Individual; Individual Differences; Knowledge; Liquid Chromatography; Locomotion; Maps; Mediating; Membrane; Mental Depression; Motor; Mus; Neurons; Outcome; Parents; Pharmacogenomics; Phenotype; Physiological; Policies; Population; Proteins; Proteome; Proteomics; Psychotropic Drugs; Public Policy; Quantitative Trait Loci; Receptor Activation; Receptor Signaling; Recombinants; Regulation; Risk; Rodent; Role; Sex Differences; Signal Pathway; Signal Transduction; Spectrometry; THC exposure; Testing; Tetrahydrocannabinol; Tissues; United States; Validation; Variant; Work; antinociception; candidate validation; cannabinoid receptor; cohort; differential expression; genetic variant; genomic locus; mRNA Expression; male; marijuana use; natural hypothermia; neurotransmission; pharmacologic; receptor; regional difference; response; sex; trafficking; trait; transcriptome; transcriptome sequencing; virtual

Cannabis is one of the most widely used psychotropic drugs in the United States and changes in public policy are expected to further increase use. Current cultivars of cannabis have been selected for high Δ9- tetrahydrocannabinol (THC) levels and THC levels have tripled over the past few decades. There is increasing evidence that use of high potency cannabis containing high levels of THC increases the risk of adverse health and behavioral consequences. Many of the specific effectors (e.g., receptors, receptor signaling pathways) mediating response to THC have not yet been fully identified and virtually nothing is known about how individual genetic differences influence response. This lack of knowledge represents a critical barrier in understanding health risks and behaviors associated with high potency cannabis use. To address these issues we have developed a powerful pharmacogenomic screen in the BXD recombinant inbred mouse population to identify gene variants in effector proteins that regulate cannabinoid 1 receptor (CB1) levels, signal transduction, termination of signaling, and/or trafficking following acute exposure to high-dose (10 mg/kg, i.p.) THC. Previously, we demonstrated strain differences in the level of the major effector of THC responses, CB1, between BXD parental strains and demonstrated heritable variation in acute responses to THC in parental strains and BXDs. We have already identified suggestive quantitative trait loci (QTLs) and candidate causal QTL genes (QTGs) in our pharmacogenomic screen using only a subset (i.e., 20) of BXDs. Here, we expand our work to identify genetic modulators of CB1 protein levels (Aim 1) and to identify and validate genetic modulators of acute responses to high-dose THC (Aim 2). In Aim 1A we use a targeted proteomics approach to quantify striatal CB1 levels in membrane-enriched protein fractions in parents, reciprocal F1, and BXD strains. Differential expression in parental strains, allele-specific expression in the F1 and linkage mapping in the BXDs will identify and validate QTLs containing trans-acting regulators of striatal CB1. In Aim 1B we extend the analysis to two other regions and in Aim 1C we include exposure to high-dose THC. In Aim 2A we screen a large panel (i.e., 80) of BXDs for differential CB1 activation quantified as hypolocomotion, hypothermia, and antinociception following VEH or THC treatment and identify QTLs accounting for at least 30% of the variation in each trait at a target precision of ±2 Mb. In Aim 2B we generate matched proteomes and transcriptomes for parental strains and F1 and generate transcriptome data for expression QTL (eQTL) mapping in BXDs with the goal of facilitating the identification of causal QTGs. In Aim 2C we validate the biological role of QTGs in cannabinoid receptor signaling pathways and responses to THC. This is the first pharmacogenomic screen to identify variation in effectors of CB1 signaling and will reveal new targets underlying responses to high-dose THC and behaviors associated with cannabis use in rodents and humans.

大麻是美国最广泛使用的精神药物之一，公共政策的变化 预计将进一步增加使用。目前的大麻品种已被选择用于高Δ9- 四氢大麻酚（THC）水平和THC水平在过去几十年中增加了两倍。人们日益 有证据表明，使用含有高水平THC的高效大麻会增加对健康不利的风险 和行为后果。许多特定的效应器（例如，受体，受体信号通路） 对THC的调解反应尚未完全确定，实际上对如何进行调解一无所知。 个体遗传差异影响反应。这种知识的缺乏是一个关键的障碍， 了解与高效力大麻使用相关的健康风险和行为。解决这些问题 我们已经在BXD重组近交系小鼠群体中开发了一种强有力的药物基因组学筛选， 鉴定调节大麻素1受体（CB 1）水平的效应蛋白中的基因变体， 在急性暴露于高剂量（10 mg/kg，i. p.） 四氢大麻酚以前，我们证明了THC反应的主要效应子CB 1水平的菌株差异， BXD亲本菌株之间的差异，并证明了亲本中对THC急性反应的遗传变异。 菌株和BXD。我们已经确定了暗示性的数量性状位点（QTL）和候选的因果关系， QTL基因（QTG）在我们的药物基因组学筛选中仅使用一个子集（即，20)的BXD。在这里，我们扩展 我们的工作是鉴定CB 1蛋白水平的遗传调节剂（目的1），并鉴定和验证遗传调节剂。 对高剂量THC的急性反应的调节剂（目的2）。在目标1A中，我们使用靶向蛋白质组学方法 定量测定亲本、正反交F1和BXD中膜富集蛋白组分中的纹状体CB 1水平 菌株亲本菌株中的差异表达，F1中的等位基因特异性表达和F1中的连锁作图。 BXD将鉴定和验证含有纹状体CB 1的反式作用调节子的QTL。在目标1B中， 将分析扩展到其他两个区域，在目标1C中，我们包括暴露于高剂量THC。在目标2A中， 筛选大的面板（即，80)BXD的差异CB 1活化定量为低运动， 在VEH或THC处理后，降低体温和抗伤害感受，并鉴定至少占 在±2 Mb的目标精度下，每个性状的变异为30%。在Aim 2B中，我们生成匹配的蛋白质组 和亲本菌株和F1的转录组，并生成表达QTL（eQTL）的转录组数据 在BXD中作图，目的是促进因果性QTG的鉴定。在目标2C中，我们验证了 QTG在大麻素受体信号传导途径和对THC的反应中的生物学作用。这是第一 药物基因组学筛选，以确定CB 1信号传导效应子的变化，并将揭示新的靶点 对高剂量THC的潜在反应以及与啮齿动物和人类使用大麻相关的行为。