MTHFD1 is critical for the negative regulation of retinoic acid receptor signalling in anencephaly
MTHFD1 is critical for the negative regulation of retinoic acid receptor signalling in anencephaly
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DOI：
10.1093/brain/awad084
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发表时间：
2023-03-16
期刊：
影响因子：
14.5
通讯作者：
Wang，Shan
中科院分区：
文献类型：
--
作者：
Xie，Xiaolu;Li，Chuang;Wang，Shan
神经管缺损是胚胎早期发育过程中由于神经管闭合失败而导致的最严重的先天性畸形，其分子机制尚不清楚。维甲酸是维生素A的一种活性衍生物，对神经系统发育至关重要，维甲酸受体（RAR）信号传导障碍已在人类神经管缺陷中观察到。然而，视黄酸-视黄酸受体在神经管缺陷中的信号调控及其机制尚不完全清楚。采用NanoString nCounter技术对11对无脑畸形胎儿、10对脑积水胎儿和9对脑膨出胎儿不同神经管缺陷表型中rars和类视黄酸X受体的mRNA表达进行了研究。采用免疫沉淀-质谱法筛选维甲酸受体γ的潜在相互作用靶点。免疫共沉淀法和免疫荧光激光共聚焦显微镜证实了蛋白间的相互作用。荧光素酶和染色质免疫沉淀与定量实时聚合酶链反应测定被用来阐明潜在的机制。此外，利用过量维甲酸构建神经管缺损动物模型，利用已建立的分子生物学技术进行进一步分析。我们报道了维甲酸受体γ (RARγ) mRNA水平在无脑畸形人胎儿脑组织中显著上调。为了进一步了解维甲酸受体γ在神经管缺陷中的作用，我们通过IP-MS筛选确定了亚甲基四氢叶酸脱氢酶1是维甲酸受体γ的特异性靶点。此外，亚甲基四氢叶酸脱氢酶1负调控视黄酸受体γ转录因子活性。此外，亚甲基四氢叶酸脱氢酶1的低表达和维甲酸受体信号的激活在人无脑畸形和维甲酸诱导的神经管缺陷小鼠模型中进一步被证实。本研究表明，单碳循环中的速率决定酶亚甲基四氢叶酸脱氢酶1可能是维甲酸受体的特异性调节因子；这些发现为神经管缺陷病理中核叶酸代谢和视黄酸受体信号传导之间的功能联系提供了新的见解。
Neural tube defects are the most severe congenital malformations that result from failure of neural tube closure during early embryonic development, and the underlying molecular mechanisms remain elusive. Retinoic acid, an active derivative of vitamin A, is critical for neural system development, and retinoic acid receptor (RAR) signalling malfunctions have been observed in human neural tube defects. However, retinoic acid–retinoic acid receptor signalling regulation and mechanisms in neural tube defects are not fully understood.The mRNA expression ofRARsand retinoid X receptors in the different human neural tube defect phenotypes, including 11 pairs of anencephaly foetuses, 10 pairs of hydrocephalus foetuses and nine pairs of encephalocele foetuses, was investigated by NanoString nCounter technology. Immunoprecipitation–mass spectrometry was performed to screen the potential interacting targets of retinoic acid receptor γ. The interactions between proteins were confirmed by co-immunoprecipitation and immunofluorescence laser confocal microscopy. Luciferase and chromatin immunoprecipitation with quantitative real-time polymerase chain reaction assays were used to clarify the underlying mechanism. Moreover, a neural tube defect animal model, constructed using excess retinoic acid, was used for further analysis with established molecular biology technologies.We report that level of retinoic acid receptor γ (RARγ) mRNA was significantly upregulated in the brain tissues of human foetuses with anencephaly. To further understand the actions of retinoic acid receptor γ in neural tube defects, methylenetetrahydrofolate dehydrogenase 1 was identified as a specific retinoic acid receptor γ target from IP–MS screening. Additionally, methylenetetrahydrofolate dehydrogenase 1 negatively regulated retinoic acid receptor γ transcription factor activity. Furthermore, low expression of methylenetetrahydrofolate dehydrogenase 1 and activation of retinoic acid receptor signalling were further determined in human anencephaly and a retinoic acid-induced neural tube defect mouse model.This study reveals that methylenetetrahydrofolate dehydrogenase 1, the rate-determining enzyme in the one-carbon cycle, might be a specific regulator of retinoic acid receptors; these findings provide new insights into the functional linkage between nuclear folate metabolism and retinoic acid receptor signalling in neural tube defect pathology.