Genetic, epigenetic and pharmacological influences modulating tissue specific regulation of the cannabinoid receptor-1 gene (CB 1 ); implications for cannabinoid pharmacogenetics
Genetic, epigenetic and pharmacological influences modulating tissue specific regulation of the cannabinoid receptor-1 gene (CB 1 ); implications for cannabinoid pharmacogenetics
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遗传、表观遗传和药理学影响调节大麻素受体 1 基因 (CB 1 ) 的组织特异性调节；
DOI：
10.1101/544585
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Hay E
中科院分区：
文献类型：
--
作者：
Hay E
大麻素受体 1 (CB1) 是对抗肥胖和药物滥用等疾病的潜在药物靶点。然而，针对 CB1（由 CNR1 基因编码）的药物试验因患者反应的差异而受到影响。为了解决控制 CNR1 表达的调控区域内的遗传和表观遗传变化导致这些差异的假设，我们分离了人类 CNR1 启动子 (CNR1prom) 并证明了其在原代细胞和转基因小鼠中的活性。我们还提供了 CNR1prom 在 CB1 自身调节及其通过 DNA 甲基化抑制中的证据。我们进一步鉴定了 CNR1 内含子 2 中的保守调控序列 (ECR1)，该序列包含与疾病相关 SNP 连锁不平衡的多态性。使用 CRISPR 基因组编辑技术删除小鼠的 ECR1，可显着降低海马体中 CNR1 的表达。这些小鼠还表现出乙醇摄入量减少和对 CB1 激动剂的低温反应。此外，人类特有的ECR1 C等位基因变体(ECR1(C))在海马细胞中驱动的CNR1prom活性水平比祖先的T等位基因更高。我们进一步证明了 AP-1 转录因子在驱动更高的 ECR1(C) 活性中的作用。在 CB1 的已知作用的背景下，当前的研究表明 ECR1(C) 可能通过一种机制在海马体中发挥神经保护作用以抵抗压力。我们的研究中使用的细胞特异性方法确定了遗传和表观遗传变化对 CNR1 基因座组织特异性调节元件活性的功能影响，这是获得大麻素药物遗传学机制理解的重要一步。
Cannabinoid receptor-1 (CB1) represents a potential drug target against conditions that include obesity and substance abuse. However, drug trials targeting CB1(encoded by the CNR1 gene) have been compromised by differences in patient response. Towards addressing the hypothesis that genetic and epigenetic changes within the regulatory regions controlling CNR1 expression contribute to these differences, we isolated the human CNR1 promotor (CNR1prom) and demonstrate its activity in primary cells and transgenic mice. We also provide evidence of CNR1prom in CB1autoregulation and its repression by DNA-methylation. We further characterised a conserved regulatory sequence (ECR1) in CNR1 intron 2 that contained a polymorphism in linkage disequilibrium with disease associated SNPs. Deletion of ECR1 from mice using CRISPR genome editing significantly reduced CNR1 expression in the hippocampus. These mice also displayed reduced ethanol intake and hypothermia response to CB1agonism. Moreover, human specific C-allele variants of ECR1 (ECR1(C)) drove higher levels of CNR1prom activity in hippocampal cells than did the ancestral T-allele. We further demonstrate a role for the AP-1 transcription factor in driving higher ECR1(C) activity. In the context of the known roles of CB1the current study suggests a mechanism through which ECR1(C) may be neuroprotective in the hippocampus against stress. The cell-specific approaches used in our study to determine the functional effects of genetic and epigenetic changes on the activity of tissue-specific regulatory elements at the CNR1 locus represent an important step in gaining a mechanistic understanding of cannabinoid pharmacogenetics.