Institute for Stem Cell Science and Regenerative Medicine, Bangalore, 560065, India.
Centre for Brain Research, Indian Institute of Science, Bangalore, 560012, India.
Sci Rep. 2022 Jul 5;12(1):11317. doi: 10.1038/s41598-022-14798-3.
Epitranscriptome modifications are crucial in translation regulation and essential for maintaining cellular homeostasis. N6 methyladenosine (mA) is one of the most abundant and well-conserved epitranscriptome modifications, which is known to play a pivotal role in diverse aspects of neuronal functions. However, the role of mA modifications with respect to activity-mediated translation regulation and synaptic plasticity has not been studied. Here, we investigated the role of mA modification in response to NMDAR stimulation. We have consistently observed that 5 min NMDAR stimulation causes an increase in eEF2 phosphorylation. Correspondingly, NMDAR stimulation caused a significant increase in the mA signal at 5 min time point, correlating with the global translation inhibition. The NMDAR induced increase in the mA signal is accompanied by the redistribution of the mA marked RNAs from translating to the non-translating pool of ribosomes. The increased mA levels are well correlated with the reduced FTO levels observed on NMDAR stimulation. Additionally, we show that inhibition of FTO prevents NMDAR mediated changes in mA levels. Overall, our results establish RNA-based molecular readout which corelates with the NMDAR-dependent translation regulation which helps in understanding changes in protein synthesis.
转录后修饰在翻译调控中至关重要，对于维持细胞内稳态也必不可少。N6 甲基腺苷（m6A）是最丰富和最保守的转录后修饰之一，已知其在神经元功能的多个方面发挥着关键作用。然而，m6A 修饰在活动介导的翻译调控和突触可塑性方面的作用尚未得到研究。在这里，我们研究了 m6A 修饰在 NMDAR 刺激下的作用。我们一致观察到，NMDAR 刺激 5 分钟会导致 eEF2 磷酸化增加。相应地，NMDAR 刺激会在 5 分钟时间点导致 m6A 信号显著增加，与全局翻译抑制相关。NMDAR 诱导的 m6A 信号增加伴随着 m6A 标记的 RNA 从翻译到核糖体非翻译池的重新分布。增加的 m6A 水平与 NMDAR 刺激时观察到的 FTO 水平降低密切相关。此外，我们还表明，抑制 FTO 可防止 NMDAR 介导的 m6A 水平变化。总的来说，我们的结果建立了一个基于 RNA 的分子读数，与 NMDAR 依赖性翻译调控相关，有助于理解蛋白质合成的变化。
