School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, Scotland, AB25 2ZD, UK.
Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK.
Mol Neurobiol. 2019 Oct;56(10):7074-7084. doi: 10.1007/s12035-019-1571-9. Epub 2019 Apr 10.
Retinoic acid (RA) regulates numerous aspects of central nervous system function through modulation of gene transcription via retinoic acid receptors (RARs). However, RA has important roles independent of gene transcription (non-genomic actions) and in the brain a crucial regulator of homeostatic plasticity is RAR control of glutamate receptor subunit 1 (GluR1) translation. An assay to quantify RAR regulation of GluR1 translation would be beneficial both to study the molecular components regulating this system and screen drugs that influence this critical mechanism for learning and memory in the brain. A bioluminescence reporter assay was developed that expresses firefly luciferase under the control of the GluR1 5' untranslated region bound by RAR. This assay was introduced into SH-SY5Y cells and used to demonstrate the role of RARα in RA regulation of GluR1 translation. A screen of synthetic RAR and RXR ligands indicated that only a subset of these ligands activated GluR1 translation. The results demonstrate the practicality of this assay to explore the contribution of RARα to this pathway and that the capacity of RAR ligands to activate translation is a quality restricted to a limited number of compounds, with implications for their RAR selectivity and potentially their specificity in drug use.
视黄酸（RA）通过视黄酸受体（RAR）调节基因转录来调节中枢神经系统功能的许多方面。然而，RA 具有独立于基因转录的重要作用（非基因组作用），在大脑中，RAR 对谷氨酸受体亚基 1（GluR1）翻译的调控是维持稳态可塑性的关键调节剂。一种定量测定 RAR 对 GluR1 翻译调控的测定方法，对于研究调节该系统的分子成分以及筛选影响大脑学习和记忆这一关键机制的药物都将是有益的。本研究开发了一种生物发光报告基因测定方法，该方法在受 RAR 结合的 GluR1 5'非翻译区控制的情况下表达萤火虫荧光素酶。该测定方法被引入 SH-SY5Y 细胞，并用于证明 RARα 在 RA 调节 GluR1 翻译中的作用。对合成 RAR 和 RXR 配体的筛选表明，只有这些配体的一部分能够激活 GluR1 翻译。这些结果证明了该测定方法的实用性，可用于探索 RARα 对该途径的贡献，并且 RAR 配体激活翻译的能力是一种质量受限的特性，这对其 RAR 选择性和潜在的药物使用特异性具有影响。
