Ethanol-induced disruption of kinase signaling pathways in brain development

乙醇诱导大脑发育中激酶信号通路的破坏

基本信息

批准号：
10366867
负责人：
ERIC Christopher OLSON
金额：
$ 36.68万
依托单位：
UPSTATE MEDICAL UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-09-19 至 2027-08-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10366867
关键词：
Actins Acute Adaptor Signaling Protein Alcohols Axon Biochemical Biological Brain Cells Centers for Disease Control and Prevention (U.S.)Child Critical Pathways Defect Dendrites Development Disease Dissection Dose Elements Embryo Enzymes Ethanol Ethanol dependence Etiology Event Fetal Alcohol Exposure Fetal Alcohol Syndrome Future Genetic Genetic Predisposition to Disease Genetic study Goals Golgi Apparatus Growth In Vitro Intellectual functioning disability Knock-out Ligand Binding Ligands Live Birth Location Membrane Methodology Molecular Molecular Target Morphology Multipolar Neuron Mus Nervous system structure Neuronal Differentiation Neurons Phase Phosphorylation Phosphotransferases Positioning Attribute Protein Dephosphorylation Protein Tyrosine Kinase Proteins Receptor Protein-Tyrosine Kinases Reelin Signaling Pathway Research Personnel Role Signal Pathway Signal Transduction Site Structure Synaptic plasticity Syndrome Teratogenic effects Testing Tyrosine Phosphorylation United States alcohol consumption during pregnancy alcohol effect alcohol exposure alcohol research alcohol response axon growth axonal pathfinding cofilin fetal glycosylation in vivo maternal alcohol use mind control novel postnatal prevent receptor receptor binding response src-Family Kinases synaptic function white matter

项目摘要

ABSTRACT Fetal Alcohol Syndrome (FAS) is one of the leading causes of intellectual disability in the United States. The CDC estimates that 0.2-1.5 per 1000 live births are children with FASD, a syndrome characterized by disrupted fetal brain development and postnatal intellectual disability (ID). Disrupted connectivity including altered dendritic structure, axonal pathfinding and white matter tracts are common findings in FAS and are thought to be major contributors to ID. However, the cellular and biological targets of alcohol are diverse and it is not clear whether there are common underlying molecular mechanisms producing these disruptions. Identification of common molecular mechanism(s) would enable a deeper understanding of this disorder, inform studies of genetic susceptibilities and provide molecular targets for neuroprotective strategies. This proposal pursues our finding that acute ethanol (EtOH) exposure disrupts Src kinase activity in embryonic cortical neurons. Src is a critical non-receptor tyrosine kinase that sits at central positions in multiple signaling pathways including the Reelin-Dab1 signaling pathway which controls brain layer formation and dendritogenesis. We found that acute EtOH exposure activates Src and induces phosphorylation of many proteins including Dab1, an essential adaptor protein in the Reelin-signaling pathway. Remarkably, this dramatic increase in phosphorylation is followed by a sustained dephosphorylation response in which the phosphorylation of Reelin effectors including Dab1, Src itself and the actin severing protein n-cofilin return to baseline levels, or below. During the extended dephosphorylation phase, the Reelin-signaling pathway can no longer be activated by in vitro application of its ligand, Reelin. In AIM 1 of this proposal, we will determine whether Reelin-Dab1 silencing occurs in vivo after maternal dosing with EtOH. We will then determine whether genetic deficiency in Src prevents the phosphorylation and dephosphorylation responses. Genetically establishing the critical kinase that initiates the EtOH response in vivo will be essential for future neuroprotective efforts. We and others have shown that Reelin-Dab1 signaling controls Golgi-deployment in the forming dendrite. In AIM 2 we will examine whether Src activation and inactivation disrupts Golgi location and function. Disrupted Golgi function would be expected to impact membrane addition, glycosylation, secretion and appropriate expression of many proteins, with potential long term negative consequences on neuritogenesis and neuronal function. In AIM 3 we will determine whether the EphA3 signaling pathway is similarly disrupted by Src dysregulation. EphA3 is a receptor tyrosine kinase that is required for axonal and white matter tract development. We identified the activation site of EphA3 as a target of EtOH-induced Src dysregulation raising the possibility that EphA3 activation and then silencing may contribute to FASD-related white matter disruptions. Collectively, these studies will determine the contribution of EtOH-dependent Src dysregulation to altered developmental signaling in pathways critical for brain development.

抽象的胎儿酒精综合症（FAS）是美国智力障碍的主要原因之一。这 CDC 估计，每 1000 名活产儿中就有 0.2-1.5 名患有 FASD，这是一种以精神紊乱为特征的综合征。胎儿大脑发育和产后智力障碍（ID）。连接中断，包括改变树突结构、轴突寻路和白质束是 FAS 的常见发现，被认为是是 ID 的主要贡献者。然而，酒精的细胞和生物学靶标是多种多样的，目前尚不清楚是否存在产生这些破坏的共同的潜在分子机制。鉴定共同的分子机制将使人们能够更深入地了解这种疾病，为以下研究提供信息遗传易感性并为神经保护策略提供分子靶点。该提案追求我们发现急性乙醇 (EtOH) 暴露会破坏胚胎皮质神经元中的 Src 激酶活性。源代码是一个关键的非受体酪氨酸激酶，位于多种信号通路的中心位置，包括 Reelin-Dab1 信号通路控制脑层形成和树突发生。我们发现急性 EtOH 暴露会激活 Src 并诱导许多蛋白质的磷酸化，包括 Dab1（一种必需的蛋白质） Reelin 信号通路中的接头蛋白。值得注意的是，磷酸化的这种急剧增加是随后是持续的去磷酸化反应，其中 Reelin 效应子的磷酸化包括 Dab1、Src 本身和肌动蛋白切断蛋白 n-cofilin 恢复到基线水平或更低。延长期间去磷酸化阶段，Reelin信号通路不能再通过体外应用其激活配体，Reelin。在本提案的AIM 1中，我们将确定Reelin-Dab1沉默后体内是否发生母亲用乙醇给药。然后我们将确定 Src 的遗传缺陷是否会阻止磷酸化和去磷酸化反应。从基因角度建立启动关键激酶体内乙醇反应对于未来的神经保护工作至关重要。我们和其他人已经证明 Reelin-Dab1 信号传导控制正在形成的树突中高尔基体的部署。在 AIM 2 中，我们将检查 Src 是否激活和失活会破坏高尔基体的位置和功能。高尔基体功能中断预计会影响许多蛋白质的膜添加、糖基化、分泌和适当表达，对神经发生和神经元功能的潜在长期负面影响。在 AIM 3 中，我们将确定 EphA3 信号通路是否同样受到 Src 失调的破坏。 EphA3 是轴突和白质束发育所需的受体酪氨酸激酶。我们确定了 EphA3 的激活位点作为 EtOH 诱导的 Src 失调的靶标，提高了 EphA3 的可能性激活然后沉默可能会导致 FASD 相关的白质破坏。总的来说，这些研究将确定 EtOH 依赖性 Src 失调对发育信号改变的影响对大脑发育至关重要的途径。