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，公共政策发生变化 预计将进一步增加当前大麻品种的选择，以实现高 Δ9- 值。 四氢大麻酚（THC）的含量在过去几十年里增加了两倍。 有证据表明使用含有高浓度 THC 的高效大麻会增加不良健康的风险 许多特定的效应器（例如受体、受体信号传导途径）。 对 THC 的调节反应尚未完全确定，并且几乎不知道如何调节 个体遗传差异会影响反应。 了解与高效大麻使用相关的健康风险和行为，以解决这些问题。 我们在 BXD 重组近交小鼠群体中开发了强大的药物基因组筛选 识别调节大麻素 1 受体 (CB1) 水平、信号的效应蛋白中的基因变异 急性暴露于高剂量（10 mg/kg，腹腔注射）后的转导、信号终止和/或运输 THC 之前，我们证明了 THC 反应的主要效应物 CB1 水平的菌株差异。 BXD 亲本品系之间存在差异，并证明亲本品系对 THC 的急性反应存在遗传变异 我们已经确定了暗示性数量性状基因座 (QTL) 和候选因果关系。 我们的药物基因组筛选中的 QTL 基因 (QTG) 仅使用 BXD 的子集（即 20 个）在此进行扩展。 我们的工作是识别 CB1 蛋白水平的遗传调节剂（目标 1）并识别和验证遗传 对高剂量 THC 的急性反应的调节剂（目标 2）。在目标 1A 中，我们使用靶向蛋白质组学方法。 量化父母、倒数 F1 和 BXD 膜富集蛋白组分中纹状体 CB1 水平 亲本菌株中的差异表达、F1 中的等位基因特异性表达和连锁图谱。 BXD 将识别并验证包含纹状体 CB1 反式作用调节因子的 QTL。 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。 筛选一大组（即 80 个）BXD，以量化为运动不足的差异 CB1 激活， VEH 或 THC 治疗后体温过低和预期，并确定 QTL 至少占 在目标精度为 ±2 Mb 的情况下，每个性状存在 30% 的变异。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 BXD 中的映射，目的是促进因果 QTG 的识别。在目标 2C 中，我们验证了 QTG 在大麻素受体信号通路和 THC 反应中的生物学作用这是第一个。 药物基因组学筛选，识别 CB1 信号传导效应子的变异，并揭示新靶点 啮齿动物和人类对高剂量 THC 的潜在反应以及与大麻使用相关的行为。