Profiling Translation in Nociceptor Plasticity

项目摘要/摘要 慢性疼痛是一种无处不在的毁灭性疾病。翻译控制是突触的主导主题 可塑性，在痛觉可塑性，特别是外周伤害性感受器的可塑性中起关键作用。信使 RNA(MRNA)受到与可塑性有关的信号通路的动态调节，如 综合应激反应(ISR)和mTOR。然而，受调控的伤害感受器中的mRNAs的身份 在塑性事件期间的翻译几乎是未知的。在这里，我们使用一种令人兴奋的新基因组学方法，称为 核糖体图谱以获得对DRG神经元中翻译控制事件的全基因组洞察。我们的预赛 研究表明，可以快速诱导特定的mRNAs子集的翻译，这些mRNAs已知参与了 背根神经节神经元对细胞因子处理的可塑性。其中就有即刻早期基因 弧形。我们认为S6K是Arc活动相关翻译所必需的。一种S6K的化学抑制剂减弱 炎症性疼痛模型中的机械超敏反应。此外，我们的初步数据还表明， 由Calca/CGRP编码的特定5‘非翻译区(UTR)阅读框翻译的证据。这个 生成的多肽能够促进体内疼痛的放大。在这项提案的第一个目标中，我们将 全面描述DRG神经元对细胞因子反应的翻译调节，重点是 潜在机制和感兴趣的目标。我们使用以下命令检查特定uORF的功能 电生理学和药理学。在第二个目标中，我们考察了甲基乙二醛(MGO)对 翻译。MGO与糖尿病神经病变以及椎间盘源性神经病变有关，我们的初步研究 数据表明，其止痛效果依赖于ISR的诱导。有趣的是，ISR诱导 UORF的翻译表明这种非规范的翻译形式是神经病理性疼痛的一个新主题。我们 将调查MGO对翻译控制的影响，并确定阻止ISR是否是 神经性疼痛。我们的实验证明了一种变革性基因组学工具的巨大潜力 以惊人的分子清晰度使人们对疼痛可塑性有新的看法。

Project Summary/Abstract Chronic pain is a pervasive and devastating condition. Translational control is a dominant theme in synaptic plasticity and plays a key role in pain plasticity, in particular the plasticity of peripheral nociceptors. Messenger RNA (mRNA) is subject to dynamic regulation by signaling pathways implicated in plasticity such as the integrated stress response (ISR) and mTOR. Yet, the identity of the mRNAs in nociceptors subjected to regulated translation during plasticity events is virtually unknown. Here, we use an exciting new genomics method termed ribosome profiling to gain genome-wide insight into translation control events in DRG neurons. Our preliminary studies reveal a rapid induction of translation of a specific subset of mRNAs that are known to be involved in neuronal plasticity in response to cytokine treatment of DRG neurons. Among them is the immediate early gene Arc. We identify S6K as required for activity dependent translation of Arc. A chemical inhibitor of S6K attenuates mechanical hypersensitivity in a model of inflammatory pain. Additionally, our preliminary data also indicate evidence for translation of a specific 5’ untranslated region (UTR) reading frame encoded by Calca/CGRP. The resulting peptide is able to promote pain amplification in vivo. In the first aim of this proposal, we will comprehensively characterize translation regulation in DRG neurons in response to cytokines with a focus on underlying mechanisms and targets of interest. We examine the function of a specific uORF with electrophysiology and pharmacology. In the second aim, we examine the effects of methylglyoxal (MGO) on translation. MGO is associated with diabetic neuropathy as well as discogenic neuropathies and our preliminary data indicate that its pain promoting effects depend on induction of the ISR. Interestingly, the ISR induces translation of uORFs suggesting this non-canonical form of translation as a new theme in neuropathic pain. We will probe the effects of MGO on translational control and determine if blocking the ISR is a viable option for neuropathic pain. Our experiments demonstrate the tremendous potential of a transformative genomics tool that enables new views on pain plasticity with astonishing molecular clarity.