Placental identified NHIP regulating neuronal oxidative stress in autism

人类胎儿大脑消耗了人体高达60%的氧气和能量， 尽管约占身体质量的13%。当胎盘对氧气的需求和 发育中的大脑供不应求，导致缺氧，随后线粒体发生变化 呼吸作用、蛋白质翻译和氧化应激。氧化应激与表观遗传机制 在胎盘-脑轴内，作用于遗传和环境风险因素的界面 自闭症谱系障碍。使用来自预期高危队列的胎盘样本，我们 最近发现并命名了一个新基因NHIP(神经元缺氧诱导，胎盘 相关)，并证明了它的表观遗传、遗传和转录与自闭症的关联。 NHIP在缺氧和神经元分化的反应中瞬时表达，两个例子 氧化应激升高。NHIP编码一种先前未发现的定位于 根据NHIP在脑内的低表达，推测它具有神经保护作用。 自闭症患者的胎盘和大脑样本与对照组进行比较。NHIP的预测结构 多肽是一种两亲性螺旋，与转录中发现的9aaTAD基序相似 许多DNA结合蛋白的激活域。我们建议检验NHIP的假设 作为多蛋白复合体的竞争性抑制物，从而保护发育中和 缺氧瞬间波后神经元的分化。因为NHIP是一个“未被发现的” 蛋白质“的功能在我们最近的研究之前还没有被描述，这一提议将集中于 关于对确定其治疗相关性至关重要的主要研究问题 NHIP。具体地说，NHIP在神经元和大脑中的作用是什么，它是如何在 对低氧的反应，以及它对神经元氧化应激的保护作用？我们提出了三个具体的 旨在使用具有良好特性的体外和体内模型，包括可诱导的人神经细胞 设计用于NHIP转录本或肽丢失的细胞系(LUHMES)，人脑提取液 已知的NHIP基因分型和表达水平，以及小鼠大脑跟随NHIP多肽 给药和/或缺氧。目标1将确定NHIP功能的分子机制 并研究NHIP丢失对蛋白质特定和全球细胞的影响。目标2将决定 NHIP如何在转录水平上对低氧诱导的氧化应激做出反应 转录因子及其与NHIP结合的遗传和表观遗传要求 促进剂和增强剂。目标3将确定外源提供的NHIP/NHIP是否保护 神经元和胚胎神经前体细胞免受低氧诱导的氧化应激。一起， 这些拟议研究的结果将提供NHIP的第一个功能特征， 一种未被研究的微肽，与自闭症谱系障碍的恢复力有关。这个 这些结果的潜在影响将是一种潜在的治疗小分子，可以用于 在自闭症和其他神经发育或缺氧相关的早期干预治疗中 精神错乱。

The human fetal brain consumes up to 60% of the body’s oxygen and energy consumption, despite making up ~13% of body mass. When the demand for oxygen in the placenta and developing brain exceeds its supply, hypoxia is induced, followed by changes to mitochondrial respiration, protein translation, and oxidative stress. Oxidative stress and epigenetic mechanisms within the placental-brain axis act at the interface of genetic and environmental risk factors in autism spectrum disorders. Using placental samples from a prospective high-risk cohort, we recently identified and named a novel gene NHIP (neuronal hypoxia inducible, placenta associated) and demonstrated its epigenetic, genetic, and transcriptional association with autism. NHIP is transiently expressed in response to hypoxia and neuronal differentiation, two examples of elevated oxidative stress. NHIP encodes a previously undiscovered micropeptide that localizes to the nucleus and is predicted to be neuroprotective, based on the lower expression of NHIP in placenta and brain samples from autism compared to control. The predicted structure of the NHIP peptide is an amphipathic helix that has similarity to a 9aaTAD motif found in transcriptional activation domains of many DNA binding proteins. We propose to test the hypothesis that NHIP acts as a competitive inhibitor of multi-protein complexes, thereby protecting developing and differentiating neurons following transient waves of hypoxia. Because NHIP is an “undiscovered protein” whose function had not been described before our recent study, this proposal will focus on the major research questions that are critical for determining the therapeutic relevance of NHIP. Specifically, what is the function of NHIP in neurons and brain, how is it regulated in response to hypoxia, and is it protective of neuronal oxidative stress? We propose three specific aims using well-characterized in vitro and in vivo models, including an inducible human neuronal cell line (LUHMES) engineered for NHIP transcript or peptide loss, human brain extracts with known NHIP genotype and expression levels, and mouse brain following NHIP peptide administration and/or hypoxia. Aim 1 will determine the molecular mechanisms of NHIP function and examine both protein-specific and global cellular impacts of NHIP loss. Aim 2 will determine how NHIP is transcriptionally responsive to hypoxia-induced oxidative stress by identifying the transcription factors and their genetic and epigenetic requirements for binding to the NHIP promoter and enhancer. Aim 3 will determine if exogenously delivered NHIP/NHIP protects neurons and embryonic neural precursor cells from hypoxia-induced oxidative stress. Together, the results from these proposed studies will provide the first functional characterization of NHIP, an understudied micropeptide that is associated with resilience to autism spectrum disorders. The potential impact of these results will be a potential therapeutic small molecule that could be used in early intervention therapy for autism and other neurodevelopmental or hypoxia-related disorders.