Effect of bromodomain inhibitors on dopamine D1R induced gene expression in striatal neurons

The dopamine D1R is Gs coupled GPCR which is expressed in striatal neurons and stimulates gene expression upon activation by dopamine or other agonists. In this work we investigated the role of the BET protein bromodomain containing protein 4 (Brd4) in mediating D1R-dependent gene expression in rat striatal neurons. Here we report the results of 3 RNA sequencing experiments. In Experiment 1 we treated primary striatal neurons with the D1R-selective agonist SKF-81297 alone or in combination with the non-selective BET inhibitor JQ1 for 60 minutes to assess the effect of BET inhibition on acute D1R-dependent gene expression. In Experiment 2, we treated primary striatal neurons with the D1R-selective agonist SKF-81297 alone or in combination with the BET bromodomain 2 selective inhibitor iBD2 for 60 minutes to determine the contribution of BD2 specifically to D1R-dependent gene expression. In Experiment 3 we treated primary striatal neurons with the D1R-selective agonist SKF-81297 alone or in combination with the non-selective BET inhibitor JQ1 for 24 hours to assess the effect of prolonged BET inhibition on basal gene expression and D1R-dependent gene expression.多巴胺D1受体（dopamine D1R）是偶联Gs蛋白的G蛋白偶联受体（G protein-coupled receptor, GPCR），在纹状体神经元中表达，被多巴胺或其他激动剂激活后可诱导基因表达。本研究探讨了BET家族蛋白含溴结构域蛋白4（bromodomain-containing protein 4, Brd4）在大鼠纹状体神经元中介导D1R依赖性基因表达中的作用。本研究共开展3组RNA测序实验：实验1中，我们用多巴胺D1受体选择性激动剂SKF-81297单独处理原代纹状体神经元，或联合非选择性BET抑制剂JQ1处理60分钟，以评估BET抑制对急性D1R依赖性基因表达的影响；实验2中，我们用多巴胺D1受体选择性激动剂SKF-81297单独处理原代纹状体神经元，或联合BET溴结构域2选择性抑制剂iBD2处理60分钟，以明确BD2结构域在D1R依赖性基因表达中的特异性贡献；实验3中，我们用多巴胺D1受体选择性激动剂SKF-81297单独处理原代纹状体神经元，或联合非选择性BET抑制剂JQ1处理24小时，以评估长期BET抑制对基础基因表达及D1R依赖性基因表达的影响。